Properties of the Number 81513

Eighty-One Thousand Five Hundred Thirteen

Basics

Value: 81512 → 81513 → 81514

Parity: odd

Prime: No

Previous Prime: 81509

Next Prime: 81517

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 3019

Divisors: 1, 3, 9, 27, 3019, 9057, 27171, 81513

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10011111001101001

Octal: 237151

Duodecimal: 3B209

Hexadecimal: 13e69

Square: 6644369169

Square Root: 285.50481607146315

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

Main diagonal of Unlucky array: a(n) = A255543(n,n). A255549

G.f.: exp( ∑_n>=1 A174468(n)*xⁿ/n ) where A174468(n) = ∑_d∣n d*σ(n/d)*σ(d). A174467

a(2)=0; for n ≠ 2, let m = A081512(n), then a(n) = value of d_n in the lexicographically earliest set of n distinct divisors d₁, ..., d_n of m with d₁ + ... + d_n = m. A81513

Number of nX4 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order. A233143