Properties of the Number 21288

Twenty-One Thousand Two Hundred Eighty-Eight

Basics

Value: 21287 → 21288 → 21289

Parity: even

Prime: No

Previous Prime: 21283

Next Prime: 21313

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 2 ³ × 3 × 887

Divisors: 1, 2, 3, 4, 6, 8, 12, 24, 887, 1774

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001100101000

Octal: 51450

Duodecimal: 103A0

Hexadecimal: 5328

Square: 453178944

Square Root: 145.9040780787158

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

T(n,k)=Number of (n+1)X(k+1) 0..6 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 12 and no adjacent elements equal. A234412

Expansion of g.f. (x²+x+1)*(2·x²+2·x+1)*(x-1)²/((1-x²-2·x³)*(x⁴+1)). A107850

G.f. A(x) satisfies: x = ∏_n>=1 (1 - xⁿ*A(x)) * (1 - x^n-1/A(x)). A356499

First differences of A000043. A134458

Number of partitions p of n such that (number of numbers in p of form 3k+2) = (number of numbers in p of form 3k). A241741

G.f. A(x) satisfies x = ∑_n>=1 A( xⁿ*(1-x)^2·n ). A380551

Number of (n+1)X(1+1) 0..6 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 12 and no adjacent elements equal. A234406

Number of (n+1)X(3+1) 0..6 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 12 and no adjacent elements equal. A234408

Number of (n+1) X (n+1) 0..2 arrays colored with the upper median value of each 2 X 2 subblock. A235946

Number of (n+1) X (7+1) 0..2 arrays colored with the upper median value of each 2 X 2 subblock. A235953