Properties of the Number 21108

Twenty-One Thousand One Hundred Eight

Basics

Value: 21107 → 21108 → 21109

Parity: even

Prime: No

Previous Prime: 21107

Next Prime: 21121

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 2 ² × 3 × 1759

Divisors: 1, 2, 3, 4, 6, 12, 1759, 3518, 5277, 7036

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001001110100

Octal: 51164

Duodecimal: 10270

Hexadecimal: 5274

Square: 445547664

Square Root: 145.28592498931204

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

The number of φ-partitions of n. A283528

Triangle read by rows: Take a hexagon with all diagonals drawn, as in A331931. Then T(n,k) = number of k-sided polygons in that figure for k = 3, 4, ..., n+4. A331932

The number of edges on a 2 by 1 ellipse formed by the straight line segments mutually connecting all points formed by dividing the ellipse into 2n equal angle sectors from its origin. A341764

Expansion of 1/(1-2·x²-3·x³). A2447

One fifth of the sum of the first n primes, when an integer. A112271

Number of walks within N² (the first quadrant of Z²) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (-1, 0), (0, -1), (0, 1), (1, -1), (1, 0)}. A151305

Array read by antidiagonals: T(n,k) is the number of non-isomorphic n X n nonnegative integer symmetric matrices with all row and column sums equal to k up to permutations of rows and columns. A333737

Number of (n+1) X (4+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically. A253452

Decimal expansion of 1/104. A21108