Properties of the Number 21888

Twenty-One Thousand Eight Hundred Eighty-Eight

Basics

Value: 21887 → 21888 → 21889

Parity: even

Prime: No

Previous Prime: 21881

Next Prime: 21893

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 2 ⁷ × 3 ² × 19

Divisors: 1, 2, 3, 4, 6, 8, 9, 12, 16, 18

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010110000000

Octal: 52600

Duodecimal: 10800

Hexadecimal: 5580

Square: 479084544

Square Root: 147.94593607125543

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

Numbers which are divisible by prime(d) for all digits d in their decimal representation. A256786

a(n) = ∑_{d∣n, n/d=1 mod 4} d³ - ∑_{d∣n, n/d=3 mod 4} d³. A50471

Numbers that are the sum of 3 positive cubes in 3 or more ways. A25398

G.f. satisfies A(x) = 1 + x·A(2·x)². A135867

Numbers that are the sum of 3 positive cubes in exactly 3 ways. A25397

T(n,k)=Number of (n+1)X(k+1) 0..4 arrays with every 2X2 subblock having the sum of the squares of all six edge and diagonal differences equal to 11 (11 maximizes T(1,1)). A234217

Expansion of (1+4·x)/((1+2·x)*(1-4·x)). A246036

Numbers k such that σ(k) AND 3·k = 3·k, where AND is bitwise-and, A004198. A388022

Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 2·x + 4. A257613

Numbers that are the sum of 3 distinct positive cubes in 3 or more ways. A25402