Properties of the Number 81856

Eighty-One Thousand Eight Hundred Fifty-Six

Basics

Value: 81855 → 81856 → 81857

Parity: even

Prime: No

Previous Prime: 81853

Next Prime: 81869

Digit Sum: 28

Digital Root: 1

Palindrome: No

Factorization: 2 ⁶ × 1279

Divisors: 1, 2, 4, 8, 16, 32, 64, 1279, 2558, 5116

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10011111111000000

Octal: 237700

Duodecimal: 3B454

Hexadecimal: 13fc0

Square: 6700404736

Square Root: 286.10487587596265

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

Triangular matrix T, read by rows, that satisfies: T = D + SHIFT_LEFT(T³), where SHIFT_LEFT shifts each row 1 place to the left and D is the diagonal matrix {1, 2, 3, ...}. A107671

Matrix cube of triangle A107671. A107676

a(n) = 20·a(n-1) - 64·a(n-2) for n > 1; a(0) = 1, a(1) = 19. A166965

a(n) = ∑_{1 <= x₁, x₂ <= n} gcd(x₁, x₂, n)⁴. A372926

Column 0 of triangle A107671. A107672

Numbers k such that 2k-1 divides 2^k-1. A81856