74 (number)

← 73 74 75 →
← 70 71 72 73 74 75 76 77 78 79 → List of numbers Integers ← 0 10 20 30 40 50 60 70 80 90 →
Cardinal	seventy-four
Ordinal	74th (seventy-fourth)
Factorization	2 × 37
Divisors	1, 2, 37, 74
Greek numeral	ΟΔ´
Roman numeral	LXXIV, lxxiv
Binary	10010102
Ternary	22023
Senary	2026
Octal	1128
Duodecimal	6212
Hexadecimal	4A16

74 (seventy-four) is the natural number following 73 and preceding 75

In mathematics

74 is:

• the twenty-first distinct semiprime ^[1] and the eleventh of the form (2.q), where q is a higher prime.
• with an aliquot sum of 40, within an aliquot sequence of three composite numbers (74, 40, 50, 43, 1,0) to the Prime in the 43-aliquot tree.
• a palindromic number in bases 6 (202₆) and 36 (22₃₆).
• a nontotient. ^[2]
• the number of collections of subsets of {1, 2, 3} that are closed under union and intersection. ^[3]
• φ(74) = φ(σ(74)). ^[4]

There are 74 different non-Hamiltonian polyhedra with a minimum number of vertices. ^[5]

References

1. Sloane, N. J. A. (ed.). "SequenceA001358". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
2. "Sloane's A005277 : Nontotients". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-29.
3. Sloane, N. J. A. (ed.). "SequenceA306445(Number of collections of subsets of {1, 2, ..., n} that are closed under union and intersection)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2022-05-22.
4. Sloane, N. J. A. (ed.). "SequenceA006872(Numbers k such that phi(k) = phi(sigma(k)))". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
5. "Sloane's A007033: Non-Hamiltonian polyhedra with n nodes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2020-12-11.