Properties of the Number 81972

Eighty-One Thousand Nine Hundred Seventy-Two

Basics

Value: 81971 → 81972 → 81973

Parity: even

Prime: No

Previous Prime: 81971

Next Prime: 81973

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 2 ² × 3 ⁴ × 11 × 23

Divisors: 1, 2, 3, 4, 6, 9, 11, 12, 18, 22

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10100000000110100

Octal: 240064

Duodecimal: 3B530

Hexadecimal: 14034

Square: 6719408784

Square Root: 286.3075269705636

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

a(n) is a non-palindromic composite located between twin primes whose reverse, which is less than it, is also located between twin primes. A103741

Infinite product of triangle A167271 columns. A167273

a(n) = n * [1 + sum(k=1 to n-1) prime(k)]. A83719

Elements of A103741 that do not terminate in a zero digit. A103764

Total length of self-avoiding walks with n bonds on the simple cubic lattice with additional bridges of length 1. A259817

a(n) = 2·n³ + 9·n² + 9·n. A303609

Poincaré series for invariant polynomial functions on the space of binary forms of degree 20. A293942

Expansion of (η(q²) / η(q))²⁴ in powers of q. A14103

Consider the geometric progression 1,1/2,1/4,1/8,1/16,1/32,1/64,... Group the terms such that the n-th group contains n terms like this (1/1),(1/2,1/4),(1/8,1/16,1,32),(1/64,1/128,1/256,1/512),... a(n) = floor(1/s(n)) where s(n) is the sum of the members of the n-th group. A81972