Properties of the Number 21315

Twenty-One Thousand Three Hundred Fifteen

Basics

Value: 21314 → 21315 → 21316

Parity: odd

Prime: No

Previous Prime: 21313

Next Prime: 21317

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 3 × 5 × 7 ² × 29

Divisors: 1, 3, 5, 7, 15, 21, 29, 35, 49, 87

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001101000011

Octal: 51503

Duodecimal: 10403

Hexadecimal: 5343

Square: 454329225

Square Root: 145.99657530229948

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

a(n) = (4·n+1)*(4·n+3). A1539

Triangle read by rows: T(n,k) is the number of sets of noncrossing paths of size k whose nodes are a subset of n nodes arranged in a circle with one node paths allowed, 0 <= k <= n. A390897

Expansion of ∏_k=1..10 (1+x^2·k-1)/(1-x^2·k). A316722

Number of partitions p of n such that median(p) > multiplicity(max(p)). A240210

a(n) = AR(n) is the total number of aperiodic k-reverses of n. A180322

Chebyshev U(n,x) polynomial evaluated at x=73 = 2·6²+1. A97728

Product of two consecutive odd numbers k, k+2 such that (k*(k+2))+-2 are primes. A174383

G.f. A(x) satisfies A(x) = 1 / ((1 - x) * (1 - 2·x * (1 + x + x² + x³) * A(x⁴))). A390658

a(n) = 49*(n-1)*(n-2)/2. A27469

Numbers such that the sum of the factorials of the digits of the fifth power is a square. A126078