Properties of the Number 21492

Twenty-One Thousand Four Hundred Ninety-Two

Basics

Value: 21491 → 21492 → 21493

Parity: even

Prime: No

Previous Prime: 21491

Next Prime: 21493

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 2 ² × 3 ³ × 199

Divisors: 1, 2, 3, 4, 6, 9, 12, 18, 27, 36

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001111110100

Octal: 51764

Duodecimal: 10530

Hexadecimal: 53f4

Square: 461906064

Square Root: 146.6015006744474

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

a(n) = -a(n-1) - a(n-2) + a(n-3), a(0)=0, a(1)=0, a(2)=1. A57597

Numbers that have exactly six prime factors counted with multiplicity (A046306) whose digit reversal is different and also has 6 prime factors (with multiplicity). A109026

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

Column 2 of triangle in A333278. A333280

Number of edges in an equilateral triangle "frame" of size n (see Comments in A328526 for definition). A333030

Row sums from A144562. A144640

Numbers k such that both k and k²/2 are averages of twin prime pairs. A152787

Lower Beatty array of the golden ratio, (1+sqrt(5))/2. A181886

Greatest integer k such that k/Fibonacci(n) <= 3/4. A293631