Properties of the Number 15920

Fifteen Thousand Nine Hundred Twenty

Basics

Value: 15919 → 15920 → 15921

Parity: even

Prime: No

Previous Prime: 15919

Next Prime: 15923

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 ⁴ × 5 × 199

Divisors: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 11111000110000

Octal: 37060

Duodecimal: 9268

Hexadecimal: 3e30

Square: 253446400

Square Root: 126.17448236470004

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 subsets of {1..n} containing n such that it is not possible to choose a different binary index of each element. A370589

Number of subsets of {2..n} containing no products of two or more distinct elements. A326116

G.f.: ∑_n>=0 xⁿ * (xⁿ + i)ⁿ / (1 + i·xⁿ⁺¹)ⁿ⁺¹, where i² = -1. A323675

Triangle T, read by rows, equal to the matrix square of triangle A117418; also equals a column bisection of triangle A117418: column 2k+1 of T^1/2 equals column k of T. A117427

Expansion of 1/((1 - x⁴ - x⁵)² - 4·x⁹). A376725

If n mod 2 = 0 then a(n) = n⁴/4 - 2·n² + 3·n; otherwise, a(n) = n⁴/4 - 2·n² + 3·n - 5/4. A64835

Row sums of the triangular array A357431. A357417

Consider the sequence b(k) such that b(k) and σ(b(k)) end with the same digit in base 10. Sequence gives values of b(k) such that b(k)/k = 10. A65255

a(n) = (35·2^(2*(3·n+2 + 2)/3) - 2*(3·n+2) - 46)/9. A116971

G.f. satisfies: A(x) = x + 2·x*A(A(x)) - x·A(x)*A(A(A(x))). A119736