Properties of the Number 20901

Twenty Thousand Nine Hundred One

Basics

Value: 20900 → 20901 → 20902

Parity: odd

Prime: No

Previous Prime: 20899

Next Prime: 20903

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 3 × 6967

Divisors: 1, 3, 6967, 20901

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000110100101

Octal: 50645

Duodecimal: 10119

Hexadecimal: 51a5

Square: 436851801

Square Root: 144.57178147895945

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(0) = 0 and a(n) = (4·n³ - 12·n² + 20·n - 9)/3 for n >= 1. A174794

Define a pair of sequences c_n, d_n by c₀=0, d₀=1 and thereafter c_n = c_n-1+d_n-1, d_n = c_n-1+4·n+2; sequence here is d_n. A192750

Invariant number of polygons of n-circum-C₅ H₅ systems. A122678

Number of zero-sum -n..n arrays of 4 elements with adjacent element differences also in -n..n. A202254

Expansion of 1/2 - (1/2)*(sqrt((2·sqrt(-3·x² - 2·x + 1) + 3·x - 2)/x)). A243255

Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 96. A31594

Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 3,1 4,1 5,2 6,2 polyhexes in any orientation on a planar nXnXn triangular grid. A155345

Partial sums of A138202. A164940

Partial sums of A255283. A255428

Greatest k such that k-th prime < 3 times n-th prime. A20901