Properties of the Number 21659

Twenty-One Thousand Six Hundred Fifty-Nine

Basics

Value: 21658 → 21659 → 21660

Parity: odd

Prime: No

Previous Prime: 21649

Next Prime: 21661

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 11 ² × 179

Divisors: 1, 11, 121, 179, 1969, 21659

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 101010010011011

Octal: 52233

Duodecimal: 1064B

Hexadecimal: 549b

Square: 469112281

Square Root: 147.16996976285617

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

Indices of primes followed by a gap (distance to next larger prime) of 44. A320720

Triangle read by rows: T(n, k) = number of hill-free Dyck paths (i.e., no peaks at height 1) of semilength n and having k peaks. A100754

Number of 11-almost primes 11ap such that 2ⁿ < 11ap <= 2ⁿ⁺¹. A120042

Numbers k such that (2·k)!/(2*(k!)²) - 1 is prime. A112861

n for which floor((3/2)ⁿ) is prime. A70759

Fibonacci sequence beginning 8, 17. A22390

Expansion of g.f. x / reversion(x - x² - x³). A217596

Fixed points of permutations A262323 and A262255. A262367

Growth function of an infinite cubic graph (number of nodes at distance <=n from fixed node). A38621

a(n) = 60·n² - 1. A158670