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Properties of the Number 21180

Twenty-One Thousand One Hundred Eighty

Basics

Value: 21179 → 21180 → 21181

Parity: even

Prime: No

Previous Prime: 21179

Next Prime: 21187

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 2 2 × 3 × 5 × 353

Divisors: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001010111100

Octal: 51274

Duodecimal: 10310

Hexadecimal: 52bc

Square: 448592400

Square Root: 145.53350129781114

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

Rectangular table, read by antidiagonals, such that the g.f. of row n, Rn(y), satisfies: Rn(y) = [ ∑k>=0 yk * Rn·k(y) ]n for n>=0, with R0(y)=1. A124550
Numbers n such that p(6n) is prime, where p(n) is the number of partitions of n. A111036
Numbers n that raised to the powers from 1 to k (with k>=1) are multiple of the sum of their digits (n raised to k+1 must not be a multiple). Case k=12. A135197
Row 4 of table A124550; also equals the self-convolution 4th power of A124564, which is row 4 of table A124560. A124554
Number of ways to choose 3 points that form an equilateral triangle from the A000292(n) points in a regular tetrahedral grid of side length n. A334581
Triangle read by rows: T(n,k) is the number of binary sequences of length n containing k subsequences 001 (n,k>=0). A118424
Number of binary sequences of length n containing exactly one subsequence 001. A118425
Least number beginning with n such that every partial sum is a square. A95158
Numbers k such that Bernoulli number Bk has denominator 56786730. A295598
a(n) is the total surface area of a hollow cubic block (defined as a block with a shell thickness of 1 cube) where n is the edge length of the removed volume. A309842