Properties of the Number 21258

Twenty-One Thousand Two Hundred Fifty-Eight

Basics

Value: 21257 → 21258 → 21259

Parity: even

Prime: No

Previous Prime: 21247

Next Prime: 21269

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 2 × 3 ² × 1181

Divisors: 1, 2, 3, 6, 9, 18, 1181, 2362, 3543, 7086

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001100001010

Octal: 51412

Duodecimal: 10376

Hexadecimal: 530a

Square: 451902564

Square Root: 145.8012345626744

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

A121153 \ A005836. A170830

Starting positions of strings of 3 0's in the decimal expansion of π. A50202

Low-temperature partition function expansion for hexagonal lattice (Potts model, q=4). A57389

a(n)=a(n-1)+a(n-2)+n+4, a(0)=0, a(1)=1. A210675

a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ... + a(n-3)*a(3) for n >= 4, with initial terms 2, -2, 1, 2. A25260

Interprimes which are of the form s·prime, s=18. A75293

Irregular triangle read by rows: row n gives for the Julian Green game with n cards labeled 1, 2, ..., n, for n >= 2, the number of games if the first removed card has label K = 2·k, for k = 1, 2, ..., floor(n/2). A348843

Decimal expansion of 1/254. A21258