Properties of the Number 71981

Seventy-One Thousand Nine Hundred Eighty-One

Basics

Value: 71980 → 71981 → 71982

Parity: odd

Prime: No

Previous Prime: 71971

Next Prime: 71983

Digit Sum: 26

Digital Root: 8

Palindrome: No

Factorization: 7 ² × 13 × 113

Divisors: 1, 7, 13, 49, 91, 113, 637, 791, 1469, 5537

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10001100100101101

Octal: 214455

Duodecimal: 357A5

Hexadecimal: 1192d

Square: 5181264361

Square Root: 268.2927505543152

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Number of connected 3-element antichains on a labeled n-set. A94034

Table read by downward diagonals: T(n,k) = number of skeleta of (3+1)-free posets with n clone sets and k tangles. A221494

Number of walks within N³ (the first octant of Z³) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (0, 1, -1), (1, 0, 0), (1, 0, 1)}. A149879

E.g.f.: exp(7·x*G(x)⁶) / G(x)⁶ where G(x) = 1 + x·G(x)⁷ is the g.f. of A002296. A251577

Parity of the digits of e in base 10. A71981