Properties of the Number 20656

Twenty Thousand Six Hundred Fifty-Six

Basics

Value: 20655 → 20656 → 20657

Parity: even

Prime: No

Previous Prime: 20641

Next Prime: 20663

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ⁴ × 1291

Divisors: 1, 2, 4, 8, 16, 1291, 2582, 5164, 10328, 20656

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101000010110000

Octal: 50260

Duodecimal: BB54

Hexadecimal: 50b0

Square: 426670336

Square Root: 143.72195378577345

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

T(n,k) = Number of n X k 0..4 arrays with every row and column running average nondecreasing rightwards and downwards. A200858

G.f.: 1 / (1 + ∑_k>=0 x^{2^k}). A339422

Series for second perpendicular moment of hexagonal lattice. A6738

Number of ways to choose a constant rooted partition of each part in a constant rooted partition of n. A301763

a(n) = -2·a(n-1) + a(n-2) + a(n-3), a(0) = -1, a(1) = -4, a(2) = 5. A321174

Numerator of Hermite(n, 4/21). A159707

Number of nondecreasing arrangements of n+2 numbers in 0..8 with the last equal to 8 and each after the second equal to the sum of one or two of the preceding four. A189325

Number of nX2 0..4 arrays with every row and column running average nondecreasing rightwards and downwards. A200852

Number of ways of 4-coloring the Fibonacci square spiral tiling of n squares with colors introduced in order. A331394

Number of nX5 0..4 arrays with every row and column running average nondecreasing rightwards and downwards. A200855