Properties of the Number 21138

Twenty-One Thousand One Hundred Thirty-Eight

Basics

Value: 21137 → 21138 → 21139

Parity: even

Prime: No

Previous Prime: 21121

Next Prime: 21139

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 2 × 3 × 13 × 271

Divisors: 1, 2, 3, 6, 13, 26, 39, 78, 271, 542

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001010010010

Octal: 51222

Duodecimal: 10296

Hexadecimal: 5292

Square: 446815044

Square Root: 145.38913301894334

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

Number of partitions of n in which the sequence of frequencies of the summands is nondecreasing. A100883

a(n) = 14·n² - 4·n. A195023

Number of partitions of an n-set without blocks of size 8. A343668

3-comma numbers: n occurs in the sequence S[k+1]=S[k]+10·last_digit(S[k-1])+first_digit(S[k]) for three different splittings n=concat(S[0],S[1]). A166513

a(n) = 680·2ⁿ - 622. A305263

Number of n-step self-avoiding walks on the Laves graph with no non-contiguous adjacencies. A344040

Fibonacci sequence beginning 2, 12. A22368

The number of 0's in the n-th stage of A164349. A164362

Number of forests of rooted trees where n dollars are spent and an n-node tree costs 2n-1 dollars. A38000

G.f.: ∑_k>=0 x^k*(k+1) / ∏_j=1..k (1 - x^2·j-1)². A376622