365 (number)

Last updated
364 365 366
Cardinal three hundred sixty-five
Ordinal 365th
(three hundred sixty-fifth)
Factorization 5 × 73
Greek numeral ΤΞΕ´
Roman numeral CCCLXV, ccclxv
Binary 1011011012
Ternary 1111123
Senary 14056
Octal 5558
Duodecimal 26512
Hexadecimal 16D16

365 (three hundred [and] sixty-five) is the natural number following 364 and preceding 366.

Contents

Mathematics

365 is a semiprime centered square number. It is also the fifth 38 -gonal number.

For multiplication, it is calculated as . Both 5 and 73 are prime numbers.

It is the smallest number that has more than one expression as a sum of consecutive square numbers:

There are no known primes with period 365, while at least one prime with each of the periods 1 to 364 is known.

Timekeeping

There are 365.2422 solar days in the mean tropical year. Several solar calendars have a year containing 365 days. [1] Related to this, in Ontario, the driver's license learner's permit used to be called "365" [2] [3] because it was valid for only 366 days. Financial and scientific calculations often use a 365-day calendar to simplify daily rates.

Related Research Articles

<span class="mw-page-title-main">Chinese calendar</span> Lunisolar calendar from China

The traditional Chinese calendar is a lunisolar calendar dating from the Han dynasty that combines solar, lunar, and other cycles for various social and agricultural purposes. While the Gregorian calendar has been adopted and adapted in various ways, and is generally the basis for China's standard civic purposes, aspects of the traditional lunisolar calendar remain, including the association of the twelve animals of the Chinese Zodiac in relation to months and years.

A leap year is a calendar year that contains an additional day compared to a common year. The 366th day is added to keep the calendar year synchronised with the astronomical year or seasonal year. Since astronomical events and seasons do not repeat in a whole number of days, calendars having a constant number of days each year will unavoidably drift over time with respect to the event that the year is supposed to track, such as seasons. By inserting ("intercalating") an additional day—a leap day—or month—a leap month—into some years, the drift between a civilization's dating system and the physical properties of the Solar System can be corrected.

<span class="mw-page-title-main">Year</span> Time of one planets orbit around a star

The year is a unit of time based on the roughly 365¼ days taken by the Earth to revolve around the Sun. The contemporary calendar year, based on the Gregorian solar calendar, approximates this cycle.

<span class="mw-page-title-main">Birthday problem</span> Probability of shared birthdays

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The Maya calendar is a system of calendars used in pre-Columbian Mesoamerica and in many modern communities in the Guatemalan highlands, Veracruz, Oaxaca and Chiapas, Mexico.

15 (fifteen) is the natural number following 14 and preceding 16.

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

The epact used to be described by medieval computists as the age of a phase of the Moon in days on 22 March; in the newer Gregorian calendar, however, the epact is reckoned as the age of the ecclesiastical moon on 1 January. Its principal use is in determining the date of Easter by computistical methods. It varies from year to year, because of the difference between the solar year of 365–366 days and the lunar year of 354–355 days.

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300 is the natural number following 299 and preceding 301.

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

360 is the natural number following 359 and preceding 361.

<span class="mw-page-title-main">Mesoamerican calendars</span>

The calendrical systems devised and used by the pre-Columbian cultures of Mesoamerica, primarily a 260-day year, were used in religious observances and social rituals, such as divination.

The Buddhist calendar is a set of lunisolar calendars primarily used in Tibet, Cambodia, Laos, Myanmar, Bangladesh, India, Sri Lanka, Thailand and Vietnam as well as in Malaysia and Singapore and by Chinese populations for religious or official occasions. While the calendars share a common lineage, they also have minor but important variations such as intercalation schedules, month names and numbering, use of cycles, etc. In Thailand, the name Buddhist Era is a year numbering system shared by the traditional Thai lunar calendar and by the Thai solar calendar.

The ISO week date system is effectively a leap week calendar system that is part of the ISO 8601 date and time standard issued by the International Organization for Standardization (ISO) since 1988 and, before that, it was defined in ISO (R) 2015 since 1971. It is used (mainly) in government and business for fiscal years, as well as in timekeeping. This was previously known as "Industrial date coding". The system specifies a week year atop the Gregorian calendar by defining a notation for ordinal weeks of the year.

<span class="mw-page-title-main">Mesoamerican Long Count calendar</span> Calendar used by several pre-Columbian Mesoamerican cultures

The Mesoamerican Long Count calendar is a non-repeating base-20 and base-18 calendar used by pre-Columbian Mesoamerican cultures, most notably the Maya. For this reason, it is often known as the MayaLong Count calendar. Using a modified vigesimal tally, the Long Count calendar identifies a day by counting the number of days passed since a mythical creation date that corresponds to August 11, 3114 BCE in the proleptic Gregorian calendar. The Long Count calendar was widely used on monuments.

The Gregorian calendar is the calendar used in most parts of the world. It went into effect in October 1582 following the papal bull Inter gravissimas issued by Pope Gregory XIII, which introduced it as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years differently so as to make the average calendar year 365.2425 days long, more closely approximating the 365.2422-day "tropical" or "solar" year that is determined by the Earth's revolution around the Sun.

Anti-sidereal time and extended-sidereal time are artificial time standards used to analyze the daily variation in the number of cosmic rays received on Earth. Anti-sidereal time has about 364.25 days per year, one day less than the number of days in a year of solar time, 365.25. Thus each anti-sidereal day is longer than a solar day by about four minutes or 24 hr 4 min. Extended-sidereal time has about 367.25 days per year, one day more than the number of days in a year of sidereal time, 366.25. Thus each extended-sidereal day is shorter than a sidereal day by about four minutes or 23 hr 52 min. All years mentioned have the same length.

<span class="mw-page-title-main">Solar Hijri calendar</span> Official calendar of Iran

The Solar Hijri calendar is the official calendar of Iran. It is a solar calendar and is the one Iranian calendar that is the most similar to the Gregorian calendar, being based on the Earth's orbit around the Sun. It begins on the March equinox as determined by the astronomical calculation for the Iran Standard Time meridian and has years of 365 or 366 days. It is sometimes also called the Shamsi calendar, Khorshidi calendar, or Persian calendar. It is abbreviated as SH, HS, AP, or, sometimes as AHSh, while the lunar Hijri calendar is usually abbreviated as AH.

References

  1. Bryan Bunch, The Kingdom of Infinite Number. New York: W. H. Freeman & Company (2000): 169
  2. "An American's Guide to Canada: Canadianisms". emily.icomm.ca. Archived from the original on 21 August 1999. Retrieved 22 May 2022.
  3. "Legislative Assembly of Ontario. Hansard". 7 September 1993. Archived from the original on 2005-12-07. Retrieved 2006-03-31.