Properties of the Number 21556

Twenty-One Thousand Five Hundred Fifty-Six

Basics

Value: 21555 → 21556 → 21557

Parity: even

Prime: No

Previous Prime: 21529

Next Prime: 21557

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ² × 17 × 317

Divisors: 1, 2, 4, 17, 34, 68, 317, 634, 1268, 5389

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 101010000110100

Octal: 52064

Duodecimal: 10584

Hexadecimal: 5434

Square: 464661136

Square Root: 146.81961721786362

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

Numbers k such that the decimal expansions of both k and k² have 1 as smallest digit and 6 as largest digit. A257197

Poincaré series for hyperbolic reflection group with Coxeter diagram shown in Comments. A265054

Expansion of x/(1 - x - 2·x³ - 2·x⁵ - x⁷). A143373

4-dimensional analog of centered polygonal numbers. A6323

Consecutive states of the linear congruential pseudo-random number generator (625·s + 6571) mod 31104 when started at s=1. A385279

Number of integer partitions of n whose product is greater than the product of their multiplicities. A353505

Number of nX4 0..1 arrays with every element equal to 0, 1 or 3 horizontally or vertically adjacent elements, with upper left element zero. A301537

Decimal expansion of 1/552. A21556