Properties of the Number 20875

Twenty Thousand Eight Hundred Seventy-Five

Basics

Value: 20874 → 20875 → 20876

Parity: odd

Prime: No

Previous Prime: 20873

Next Prime: 20879

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 5 ³ × 167

Divisors: 1, 5, 25, 125, 167, 835, 4175, 20875

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000110001011

Octal: 50613

Duodecimal: 100B7

Hexadecimal: 518b

Square: 435765625

Square Root: 144.4818327679989

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 A(n,k) of rooted trees with n nodes and k-colored non-root nodes; square array A(n,k), n>=0, k>=0, read by antidiagonals. A242249

Number of directed rooted trees with n nodes. A6964

The least number with exactly n ones in the continued fraction of its square root. A206578

Number of partitions p of n such that min(p) <= (number of parts of p) < max(p). A325341

a(n) = (3·n - 1)*(4·n - 1). A33578

Number of n X 5 binary arrays with every 1 having exactly three king-move neighbors equal to 1. A183452

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 45 ones. A31813

Row sums of triangle A091604. A91610

T(n,k) = Number of n X k binary arrays with every 1 having exactly three king-move neighbors equal to 1. A183456

Triangle read by rows: T(n,k) is the number of permutations of {1..n} at Kendall τ distance k of permutation sigma1 and k+1 Kendall τ distance of permutation sigma2, where sigma1 and sigma2 are at Kendall τ distance 1. A307429