Properties of the Number 81861

Eighty-One Thousand Eight Hundred Sixty-One

Basics

Value: 81860 → 81861 → 81862

Parity: odd

Prime: No

Previous Prime: 81853

Next Prime: 81869

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 13 × 2099

Divisors: 1, 3, 13, 39, 2099, 6297, 27287, 81861

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10011111111000101

Octal: 237705

Duodecimal: 3B459

Hexadecimal: 13fc5

Square: 6701223321

Square Root: 286.1136137970369

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 n X 5 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. A280437

a(n) = (1/24)*(sigma₃(2·n-1) - sigma₁(2·n-1)). A81861