Properties of the Number 20644

Twenty Thousand Six Hundred Forty-Four

Basics

Value: 20643 → 20644 → 20645

Parity: even

Prime: No

Previous Prime: 20641

Next Prime: 20663

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 ² × 13 × 397

Divisors: 1, 2, 4, 13, 26, 52, 397, 794, 1588, 5161

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101000010100100

Octal: 50244

Duodecimal: BB44

Hexadecimal: 50a4

Square: 426174736

Square Root: 143.68020044529447

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 n such that Bernoulli number B_n has denominator 1590. A272140

Number of balanced reduced multisystems with n atoms all equal to 1. A318813

Number of balanced reduced multisystems whose atoms cover an initial interval of positive integers with multiplicities equal to the prime indices of n. A318846

Number of non-isomorphic balanced reduced multisystems whose degrees (atom multiplicities) are the weakly decreasing prime indices of n. A330666

Index of first occurrence of n-th prime in A001203, the continued fraction for π. A107892

Triangle read by rows: T(n,k) is the number of balanced reduced multisystems of weight n with atoms colored using exactly k colors. A330776

a(n) = Bell(n) - 2ⁿ + n. A144646

Number of compositions of n into distinct parts where each part i is marked with a word of length i over a binary alphabet whose letters appear in alphabetical order and all letters occur at least once in the composition. A261853

a(n)-th nonsquarefree is sum of first k nonsquarefrees for some k. A20644