Properties of the Number 23181

Twenty-Three Thousand One Hundred Eighty-One

Basics

Value: 23180 → 23181 → 23182

Parity: odd

Prime: No

Previous Prime: 23173

Next Prime: 23189

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 7727

Divisors: 1, 3, 7727, 23181

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101101010001101

Octal: 55215

Duodecimal: 114B9

Hexadecimal: 5a8d

Square: 537358761

Square Root: 152.2530787866045

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

Number of vertices formed by drawing the lines connecting any two of the 2*(n+2) perimeter points of a 3 X (n+1) rectangular grid of points (or equally, a 2 X n grid of squares). A331763

Wiener index of a benzenoid consisting of a spiral chain of n hexagons (s=1; see the Gutman et al. reference). A193391

T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 3, 4, 5 or 7 king-move adjacent elements, with upper left element zero. A305918

G.f.: ∑_n>=0 (xⁿ - 1)ⁿ * xⁿ / (1-x)ⁿ⁺¹. A243919

Semiprimes in A054567. A113692

Numbers k such that (k!-8)/8 is prime. A139203

a(n) = 16·n² + 2·n + 1. A204675

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 84 ones. A31852

Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 4, 5 or 7 king-move adjacent elements, with upper left element zero. A305914

Expansion of ∑_{p prime, i>=2} x^pⁱ/(1 - x^pⁱ) / ∏_j>=1 (1 - x^j). A281611