Properties of the Number 21621

Twenty-One Thousand Six Hundred Twenty-One

Basics

Value: 21620 → 21621 → 21622

Parity: odd

Prime: No

Previous Prime: 21617

Next Prime: 21647

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 3 × 7207

Divisors: 1, 3, 7207, 21621

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101010001110101

Octal: 52165

Duodecimal: 10619

Hexadecimal: 5475

Square: 467467641

Square Root: 147.0408106615303

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 integer partitions of n without an alternating permutation. A345165

Numbers that are the sum of seven fourth powers in six or more ways. A345572

Numbers that are the sum of seven fourth powers in exactly six ways. A345828

Trajectory of 18 under iteration of the map k -> A087712(k). A77960

Number of partitions of n into parts not of the form 25k, 25k+12 or 25k-12. Also number of partitions with at most 11 parts of size 1 and differences between parts at distance 11 are greater than 1. A36011

Numbers k such that k and k² use only the digits 1, 2, 4, 6 and 7. A136993

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 98. A31596

Decimal expansion of 1/617. A21621