12 (number)

Last updated
11 12 13
Cardinal twelve
Ordinal 12th
(twelfth)
Numeral system duodecimal
Factorization 22 × 3
Divisors 1, 2, 3, 4, 6, 12
Greek numeral ΙΒ´
Roman numeral XII
Greek prefix dodeca-
Latin prefix duodeca-
Binary 11002
Ternary 1103
Senary 206
Octal 148
Duodecimal 1012
Hexadecimal C16
Malayalam ൰൨
Bengali ১২
Hebrew numeral י"ב
Babylonian numeral 𒌋𒐖

12 (twelve) is the natural number following 11 and preceding 13.

Contents

Twelve is the 3rd superior highly composite number, [1] the 3rd colossally abundant number, [2] the 5th highly composite number, and is divisible by the numbers from 1 to 4, and 6, a large number of divisors comparatively.

It is central to many systems of timekeeping, including the Western calendar and units of time of day, and frequently appears in the world's major religions.

Name

Twelve is the largest number with a single-syllable name in English. Early Germanic numbers have been theorized to have been non-decimal: evidence includes the unusual phrasing of eleven and twelve, the former use of "hundred" to refer to groups of 120, and the presence of glosses such as "tentywise" or "ten-count" in medieval texts showing that writers could not presume their readers would normally understand them that way. [3] [4] [5] Such uses gradually disappeared with the introduction of Arabic numerals during the 12th-century Renaissance.

Derived from Old English, twelf and tuelf are first attested in the 10th-century Lindisfarne Gospels' Book of John. [note 1] [7] It has cognates in every Germanic language (e.g. German zwölf), whose Proto-Germanic ancestor has been reconstructed as *twaliƀi..., from *twa ("two") and suffix *-lif- or *-liƀ- of uncertain meaning. [7] It is sometimes compared with the Lithuanian dvýlika, although -lika is used as the suffix for all numbers from 11 to 19 (analogous to "-teen"). [7] Every other Indo-European language instead uses a form of "two"+"ten", such as the Latin duōdecim. [7] The usual ordinal form is "twelfth" but "dozenth" or "duodecimal" (from the Latin word) is also used in some contexts, particularly base-12 numeration. Similarly, a group of twelve things is usually a "dozen" but may also be referred to as a "dodecad" or "duodecad". The adjective referring to a group of twelve is "duodecuple".

As with eleven, [8] the earliest forms of twelve are often considered to be connected with Proto-Germanic *liƀan or *liƀan ("to leave"), with the implicit meaning that "two is left" after having already counted to ten. [7] The Lithuanian suffix is also considered to share a similar development. [7] The suffix *-lif- has also been connected with reconstructions of the Proto-Germanic for ten. [8] [9]

As mentioned above, 12 has its own name in Germanic languages such as English (dozen), Dutch (dozijn), German (Dutzend), and Swedish (dussin), all derived from Old French dozaine. It is a compound number in many other languages, e.g. Italian dodici (but in Spanish and Portuguese, 16, and in French, 17 is the first compound number),[ dubious discuss ] Japanese 十二 jūni.[ clarification needed ]

Written representation

In prose writing, twelve, being the last single-syllable numeral, is sometimes taken as the last number to be written as a word, and 13 the first to be written using digits. This is not a binding rule, and in English language tradition, it is sometimes recommended to spell out numbers up to and including either nine, ten or twelve, or even ninety-nine or one hundred. Another system spells out all numbers written in one or two words (sixteen, twenty-seven, fifteen thousand, but 372 or 15,001). [10] In German orthography, there used to be the widely followed (but unofficial) rule of spelling out numbers up to twelve (zwölf). The Duden [ year needed ] (the German standard dictionary) mentions this rule as outdated.

In mathematics

12 is a composite number, the smallest abundant number, a semiperfect number, [11] a highly composite number, [12] a refactorable number, [13] and a Pell number. [14] It is the smallest of two known sublime numbers, numbers that have a perfect number of divisors whose sum is also perfect. [15]

There are twelve Jacobian elliptic functions and twelve cubic distance-transitive graphs.

A twelve-sided polygon is a dodecagon. In its regular form, it is the largest polygon that can uniformly tile the plane alongside other regular polygons, as with the truncated hexagonal tiling or the truncated trihexagonal tiling. [16]

A regular dodecahedron has twelve pentagonal faces. Regular cubes and octahedrons both have 12 edges, while regular icosahedrons have 12 vertices.

The densest three-dimensional lattice sphere packing has each sphere touching twelve other spheres, and this is almost certainly true for any arrangement of spheres (the Kepler conjecture). Twelve is also the kissing number in three dimensions.

There are twelve complex apeirotopes in dimensions five and higher, which include van Oss polytopes in the form of complex -orthoplexes. [17] There are also twelve paracompact hyperbolic Coxeter groups of uniform polytopes in five-dimensional space.

Bring's curve is a Riemann surface of genus four, with a domain that is a regular hyperbolic 20-sided icosagon. [18] By the Gauss-Bonnet theorem, the area of this fundamental polygon is equal to .

Twelve is the smallest weight for which a cusp form exists. This cusp form is the discriminant whose Fourier coefficients are given by the Ramanujan -function and which is (up to a constant multiplier) the 24th power of the Dedekind eta function:

This fact is related to a constellation of interesting appearances of the number twelve in mathematics ranging from the fact that the abelianization of special linear group has twelve elements, to the value of the Riemann zeta function at being , which stems from the Ramanujan summation

Although the series is divergent, methods such as Ramanujan summation can assign finite values to divergent series.

List of basic calculations

Multiplication 12345678910111213141516171819202122232425501001000
12 × x12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 228 240 252 264 276 288 300 600 120012000
Division 12345678910111213141516
12 ÷ x126432.421.7142851.51.31.21.0910.9230760.8571420.80.75
x ÷ 120.0830.160.250.30.4160.50.5830.60.750.830.91611.0831.161.251.3
Exponentiation 123456789101112
12x121441728207362488322985984358318084299816965159780352619173642247430083706888916100448256
x12140965314411677721624414062521767823361384128720168719476736282429536481100000000000031384283767218916100448256

In other bases

The duodecimal system (1210 [twelve] = 1012), which is the use of 12 as a division factor for many ancient and medieval weights and measures, including hours, probably originates from Mesopotamia.

In nature

Notably, twelve is the number of full lunations in a solar year, hence the number of months in a solar calendar, as well as the number of signs in the Western, Islamic and the Chinese zodiac. Twelve is also the number of years for an orbital period of Jupiter.

Religion

The number twelve carries religious, mythological and magical symbolism; since antiquity, the number has generally represented perfection, entirety, or cosmic order. [19]

Ancient Greek religion

Judaism and Christianity

Ishmael – the first-born son of Abraham – has 12 sons/princes (Genesis 25:16), and Jacob also has 12 sons, who are the progenitors of the Twelve Tribes of Israel. [21] This is reflected in Christian tradition, notably in the twelve Apostles. When Judas Iscariot is disgraced, a meeting is held (Acts) to add Saint Matthias to complete the number twelve once more. The Book of Revelation contains much numerical symbolism, and many of the numbers mentioned have 12 as a divisor. 12:1 mentions a womaninterpreted as the people of Israel, the Church and the Virgin Mary wearing a crown of twelve stars (representing each of the twelve tribes of Israel). Furthermore, there are 12,000 people sealed from each of the twelve tribes of Israel (the Tribe of Dan is omitted while Manasseh is mentioned), making a total of 144,000 (which is the square of 12 multiplied by a thousand).

12 was the only number considered to be religiously divine in the 1600s causing many Catholics to wear 12 buttons to church every Sunday. Some extremely devout Catholics would always wear this number of buttons to any occasion on any type of clothing.[ citation needed ]

Islam

Twelve is referred to in a few different verses of the Quran. Two are in reference to the Twelve Tribes of Israel.

And ˹remember˺ when Moses prayed for water for his people, We said, "Strike the rock with your staff." Then twelve springs gushed out, ˹and˺ each tribe knew its drinking place. ˹We then said,˺ "Eat and drink of Allah’s provisions, and do not go about spreading corruption in the land."

Surah Al-Baqarah (The Heifer):60 [22]

The second reference is:

We divided them into twelve tribes—each as a community. And We revealed to Moses, when his people asked for water, "Strike the rock with your staff." Then twelve springs gushed out. Each tribe knew its drinking place. We shaded them with clouds and sent down to them manna and quails,1 ˹saying˺, "Eat from the good things We have provided for you." They ˹certainly˺ did not wrong Us, but wronged themselves.

Surah Al-A'raf (The Heights):160 [23]

Note 1: Manna (heavenly bread) and quails (chicken-like birds) sustained the children of Israel in the wilderness after they left Egypt.

The third reference is to the number of months and the sacred ones amongst them:

Indeed, the number of months with Allāh is twelve [lunar] months in the register of Allāh [from] the day He created the heavens and the earth; of these, four are sacred.2

Surah At-Tawbah (The Repentance):36 [24]

Note 2: The four sacred months of the Islamic calendar are Dhu al-Qa'dah, Dhu al-Hijjah, Muharram, and Rajab (months 11, 12, 1 and 7).

Hinduism

Others

Ancient Hittite relief carving from Yazilikaya, a sanctuary at Hattusa, depicting twelve gods of the underworld Yazilikaya B 12erGruppe.jpg
Ancient Hittite relief carving from Yazılıkaya, a sanctuary at Hattusa, depicting twelve gods of the underworld

Law

Timekeeping

In numeral systems

۱۲ Arabic ១២ Khmer ԺԲ Armenian
১২ Bangla ΔΙΙ Attic Greek 𝋬 Maya
יב Hebrew
12 (number)12 (number)12 (number)
Egyptian
१२ Indian and Nepali (Devanāgarī)十二 Chinese and Japanese
௧௨ Tamil XII Roman and Etruscan
๑๒ Thai IIX Chuvash
౧౨ Telugu and Kannada ١٢ Urdu
ιβʹ Ionian Greek ൧൨ Malayalam

In science

Image of the globular cluster Messier 12 by Hubble Space Telescope Messier 12 Hubble WikiSky.jpg
Image of the globular cluster Messier 12 by Hubble Space Telescope

In sports

In technology

In the arts

Film

Films with the number twelve or its variations in their titles include:

Television

Theatre

Literature

Comics

  • Apocalypse: The Twelve, a comic book crossover in Marvel Comics. The connection between Apocalypse and twelve specific mutants is revisitied in the 2024 limited series, X-Men: Heir to Apocalypse.

Music

Music theory

Pop music

Art theory

Games

In other fields

12 stars are featured on the Flag of Europe. Flag of Europe.svg
12 stars are featured on the Flag of Europe.

See also

Notes

  1. Specially, a passage referring to Judas Iscariot as "one of the twelve" (an of ðæm tuelfum). [6]

Related Research Articles

21 (twenty-one) is the natural number following 20 and preceding 22.

33 (thirty-three) is the natural number following 32 and preceding 34.

90 (ninety) is the natural number following 89 and preceding 91.

29 (twenty-nine) is the natural number following 28 and preceding 30. It is a prime number.

72 (seventy-two) is the natural number following 71 and preceding 73. It is half a gross or six dozen.

84 (eighty-four) is the natural number following 83 and preceding 85. It is seven dozens.

34 (thirty-four) is the natural number following 33 and preceding 35.

58 (fifty-eight) is the natural number following 57 and preceding 59.

92 (ninety-two) is the natural number following 91 and preceding 93

<span class="mw-page-title-main">360 (number)</span> Natural number

360 is the natural number following 359 and preceding 361.

126 is the natural number following 125 and preceding 127.

132 is the natural number following 131 and preceding 133. It is 11 dozens.

135 is the natural number following 134 and preceding 136.

<span class="mw-page-title-main">1,000,000,000</span> Natural number

1,000,000,000 is the natural number following 999,999,999 and preceding 1,000,000,001. With a number, "billion" can be abbreviated as b, bil or bn.

168 is the natural number following 167 and preceding 169.

177 is the natural number following 176 and preceding 178.

1728 is the natural number following 1727 and preceding 1729. It is a dozen gross, or one great gross. It is also the number of cubic inches in a cubic foot.

288 is the natural number following 287 and preceding 289. Because 288 = 2 · 12 · 12, it may also be called "two gross" or "two dozen dozen".

20,000 is the natural number that comes after 19,999 and before 20,001.

888 is the natural number following 887 and preceding 889.

References

  1. "A002201 - OEIS". oeis.org. Retrieved 2024-11-28.
  2. "A004490 - OEIS". oeis.org. Retrieved 2024-11-28.
  3. Gordon, E. V. (1957). Introduction to Old Norse. Oxford, England: Clarendon Press. pp. 292–293. Archived from the original on 2016-04-15. Retrieved 2017-09-08.
  4. Stevenson, W. H. (December 1899). "The Long Hundred and its Use in England". Archaeological Review. 4 (5): 313–317.
  5. Goodare, Julian (1994). "The long hundred in medieval and early modern Scotland" (PDF). Proceedings of the Society of Antiquaries of Scotland. 123: 395–418. doi:10.9750/PSAS.123.395.418. S2CID   162146336.
  6. John 6:71.
  7. 1 2 3 4 5 6 Oxford English Dictionary, 1st ed. "twelve, adj. and n." Oxford University Press (Oxford), 1916.
  8. 1 2 Oxford English Dictionary, 1st ed. "eleven, adj. and n." Oxford University Press (Oxford), 1891.
  9. Dantzig, Tobias (1930), Number: The Language of Science.
  10. "Numbers: Writing Numbers // Purdue Writing Lab". Purdue Writing Lab. Retrieved 25 February 2020.
  11. Sloane, N. J. A. (ed.). "SequenceA005835(Pseudoperfect (or semiperfect) numbers n: some subset of the proper divisors of n sums to n.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2016-06-01.
  12. Sloane, N. J. A. (ed.). "SequenceA002182(Highly composite numbers, definition (1): numbers n where d(n), the number of divisors of n (A000005), increases to a record.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-06-19.
  13. Sloane, N. J. A. (ed.). "SequenceA033950(Refactorable numbers: number of divisors of k divides k. Also known as tau numbers.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-06-15.
  14. Sloane, N. J. A. (ed.). "SequenceA000129(Pell numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-01-10.
  15. "Sloane's A081357 : Sublime numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-01.
  16. Grünbaum, Branko; Shephard, G. C. (1987). "Section 2.1: Regular and uniform tilings". Tilings and Patterns . New York: W. H. Freeman and Company. p. 59. doi:10.2307/2323457. ISBN   0-7167-1193-1. JSTOR   2323457. OCLC   13092426. S2CID   119730123.
  17. H. S. M. Coxeter (1991). Regular Complex Polytopes (2 ed.). Cambridge University Press. pp. 144–146. doi:10.2307/3617711. ISBN   978-0-521-39490-1. JSTOR   3617711. S2CID   116900933. Zbl   0732.51002.
  18. Weber, Matthias (2005). "Kepler's small stellated dodecahedron as a Riemann surface" (PDF). Pacific Journal of Mathematics . 220 (1): 172. doi: 10.2140/pjm.2005.220.167 . MR   2195068. S2CID   54518859. Zbl   1100.30036.
  19. Drews (1972), p. 43, n. 10.
  20. Weinreich, Th., "Zwölfgötter", Ausführliches Lexikon der Griechischen und Römischen Mythologie, vol. VI, col. 764-848.
  21. "And it is thought that there is a special significance in the number twelve. It was typified, we know, by many things in the Old Testament; by the twelve sons of Jacob, by the twelve princes of the children of Israel, by the twelve fountains in Elim, by the twelve stones in Aaron's breast-plate, by the twelve loaves of the shew-bread, by the twelve spies sent by Moses, by the twelve stones of which the altar was made, by the twelve stones taken out of Jordan, by the twelve oxen which bare" P. Young, Daily readings for a year (1863), p. 150.
  22. "Surah Al-Baqarah - 60". Quran.com. Retrieved 2023-08-02.
  23. "Surah Al-A'raf - 160". Quran.com. Retrieved 2023-08-02.
  24. "Surah At-Tawbah - 36". Quran.com. Retrieved 2023-08-02.
  25. Collins 2002, p.  228.
  26. Benet's Reader's Encyclopedia, 3d ed.
  27. "Lunar versus solar calendar".
  28. Attia, Peter (2018-09-05). "The Full History of Board Games". Medium. Retrieved 2020-10-22.
  29. "Shilling | currency". Encyclopedia Britannica. Retrieved 20 May 2021.

Sources

Further reading

Books

Journal articles