Properties of the Number 20643

Twenty Thousand Six Hundred Forty-Three

Basics

Value: 20642 → 20643 → 20644

Parity: odd

Prime: No

Previous Prime: 20641

Next Prime: 20663

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 7 × 983

Divisors: 1, 3, 7, 21, 983, 2949, 6881, 20643

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000010100011

Octal: 50243

Duodecimal: BB43

Hexadecimal: 50a3

Square: 426133449

Square Root: 143.67672045254932

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

Powers of cube root of 2 rounded up. A17981

Powers of cube root of 2 rounded to nearest integer. A17980

Positions of 3's in A264977; positions of 6's in A277330. A277713

Numbers that match polynomials over {0,1} that have a factor containing -3 as a coefficient; see Comments. A208182

Triangle where g.f. of row n = ∏_i=0..n [F(i+1) + F(i)*x] for n>=0, where F(i) = A000045(i) is the i-th Fibonacci number. A130405

Revert transform of 2·x*(1-x-x³-x⁵+x⁶)-x/(1+x). A49186

Number of 3 X n binary matrices with distinct rows, up to row and column permutation; (n,3)-hypergraphs (including empty hyperedge but excluding multiple hyperedges). A55194

Number of primitive (aperiodic) word structures of length n using a 6-ary alphabet. A56277

Expansion of 1/(1-x-x⁴-x⁶). A120446

Numbers k such that 64·k⁶ + 1091 is prime. A155809