Properties of the Number 20945

Twenty Thousand Nine Hundred Forty-Five

Basics

Value: 20944 → 20945 → 20946

Parity: odd

Prime: No

Previous Prime: 20939

Next Prime: 20947

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 5 × 59 × 71

Divisors: 1, 5, 59, 71, 295, 355, 4189, 20945

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101000111010001

Octal: 50721

Duodecimal: 10155

Hexadecimal: 51d1

Square: 438693025

Square Root: 144.72387501722028

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

Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 966", based on the 5-celled von Neumann neighborhood. A284538

One-fourth of fourth column of Lucas bisection triangle (odd part). A61173

(Prime(prime(n))²-1)/24. A92772

Number of (n+3)X(n+3) binary arrays with every 4X4 subblock commuting with each horizontal and vertical neighbor 4X4 subblock. A188096

T(n,k)=Number of (n+3)X(k+3) binary arrays with every 4X4 subblock commuting with each horizontal and vertical neighbor 4X4 subblock. A188105

a(2n+1) = |a(2n) - a(2n-1)|, a(2n) = a(n) + a(n-1). A20945