Properties of the Number 21928

Twenty-One Thousand Nine Hundred Twenty-Eight

Basics

Value: 21927 → 21928 → 21929

Parity: even

Prime: No

Previous Prime: 21911

Next Prime: 21929

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 2 ³ × 2741

Divisors: 1, 2, 4, 8, 2741, 5482, 10964, 21928

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010110101000

Octal: 52650

Duodecimal: 10834

Hexadecimal: 55a8

Square: 480837184

Square Root: 148.08105888330215

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 where the difference between consecutive parts is at most 9. A238869

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with the minimum plus the upper median equal to the lower median plus the maximum in every 2X2 subblock. A235893

T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 5 6 or 7. A252201

a(n) = number of steps to reach 0 when starting from k = (n³)-1 and repeatedly applying the map that replaces k with k - A055401(k), where A055401(k) = the number of positive cubes needed to sum to k using the greedy algorithm. A261228

Number of isomorphism classes of nanocones with 4 pentagons and a nearsymmetric boundary of length n. A198016

Numbers that are the sum of seven fifth powers in two or more ways. A345605

Numbers that are the sum of seven fifth powers in exactly two ways. A346279

Numbers that are midway between the nearest square and the nearest cube. A233075

a(n) = (∑_k=1..n A073698(k))^1/n. A93928

Numbers k such that 13·4^k + 1 is prime. A2257