Properties of the Number 28015

Twenty-Eight Thousand Fifteen

Basics

Value: 28014 → 28015 → 28016

Parity: odd

Prime: No

Previous Prime: 28001

Next Prime: 28019

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 5 × 13 × 431

Divisors: 1, 5, 13, 65, 431, 2155, 5603, 28015

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110110101101111

Octal: 66557

Duodecimal: 14267

Hexadecimal: 6d6f

Square: 784840225

Square Root: 167.37682037845025

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

Expansion of x*(1-2·x)/((1-x)*(1+2·x)*(1-6·x)). A91055

E.g.f.: x / LambertW( x/(1-x) ). A352411

Numerator of n*(n-3)*(3·n²-6·n+2)/(3*(n-1)*(n-2)). A23417

Numbers n such that φ((prime(n)+1)/2)=σ(n). A68473

a(n) = 2 + floor((1 + ∑_j=1..n-1 a(j))/4). A120161

Positive heptagonal numbers (A000566) that are pentagonal numbers (A000326) divided by 2. A259165

Expansion of 1/((1-2x)(1-8x)(1-9x)(1-10x)). A28015

Number of (n+1)X(5+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or vertically, with no adjacent elements equal. A232403

Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum 1 and no antidiagonal sum 2 and no row sum 0 and no column sum 0. A255085