Properties of the Number 21808

Twenty-One Thousand Eight Hundred Eight

Basics

Value: 21807 → 21808 → 21809

Parity: even

Prime: No

Previous Prime: 21803

Next Prime: 21817

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ⁴ × 29 × 47

Divisors: 1, 2, 4, 8, 16, 29, 47, 58, 94, 116

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010100110000

Octal: 52460

Duodecimal: 10754

Hexadecimal: 5530

Square: 475588864

Square Root: 147.67531953579785

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 into 7 distinct and relatively prime parts. A339672

dot product (n,n-1,...2,1).(3,4,...,n,1,2). A26054

Number of step shifted (decimated) sequence structures using a maximum of five different symbols. A56394

Number of n X n matrices with entries {0,1} that are diagonalizable over the real numbers. A91504

Number of permutations of 1..n with displacements restricted to {-5,-4,-1,0,2,3}. A189591

Numbers n such that the Collatz iterations for n and n + 1 have the same length (A078417) but do not meet a certain condition. (See comments.) A274410

Sum of the asymmetry degrees of all compositions of n into parts congruent to 1 mod 3. A276061

Cogrowth sequence of the 12-element group A4 = <S,T | S³, T², (ST)³>. A377626

Decimal expansion of 1/804. A21808