Properties of the Number 21524

Twenty-One Thousand Five Hundred Twenty-Four

Basics

Value: 21523 → 21524 → 21525

Parity: even

Prime: No

Previous Prime: 21523

Next Prime: 21529

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 2 ² × 5381

Divisors: 1, 2, 4, 5381, 10762, 21524

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010000010100

Octal: 52024

Duodecimal: 10558

Hexadecimal: 5414

Square: 463282576

Square Root: 146.71059948074645

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 number of parts divides n. A67538

Triangle read by rows: T(n,k) = number of nonequivalent dissections of an n-gon into k polygons by nonintersecting diagonals up to rotation and reflection. A295634

Partial sums of ∑_k=1..n n/gcd(n,k), or partial sums of ∑_d∣n d*φ(d) (see A057660). A174405

Triangular array T(n,k), read by rows: coefficients of strong divisibility sequence of polynomials p(1,x) = 1, p(2,x) = 1 + 3·x, p(n,x) = u·p(n-1,x) + v·p(n-2,x) for n >= 3, where u = p(2,x), v = 3 - x². A368152

a(n) equals the (n*(n+1)/2)-th partial sum of the self-convolution cube of A010054, which has the g.f.: ∑_k>=0 x^k*(k+1/2). A109414

Coordination sequence for MgNi2, Position Mg2. A9935

a(n) = n³/6 + 3·n²/4 + 7·n/3 + 7/8 + (-1)ⁿ/8. A173154

A sequence related to Le Corbusier's Modulor: round(φ^{-13 + n}*175). A227572

Number of (n+2) X (2+2) 0..1 arrays with every 2 X 2 and 3X3 subblock diagonal maximum minus antidiagonal minimum nondecreasing horizontally and vertically. A253504

Number of length-n binary strings having a string attractor of size at most 2. A355520