Properties of the Number 21631

Twenty-One Thousand Six Hundred Thirty-One

Basics

Value: 21630 → 21631 → 21632

Parity: odd

Prime: No

Previous Prime: 21617

Next Prime: 21647

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 97 × 223

Divisors: 1, 97, 223, 21631

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101010001111111

Octal: 52177

Duodecimal: 10627

Hexadecimal: 547f

Square: 467900161

Square Root: 147.0748108956799

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

T(n,k)=Number of length n+2 0..k arrays with no consecutive three elements summing to more than k. A241619

Main diagonal of array in A083140. A83141

a(n) = 32·n² - 1. A158563

a(n) is the number of rooted binary trees with minimal Sackin index and n leaves. A299037

Bases in which 13 is a unique-period prime. A306077

Numbers k such that hexagonal number H(k) is the sum of two consecutive hexagonal numbers. A251602

Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 603", based on the 5-celled von Neumann neighborhood. A289882

Number of (w,x,y) with all terms in {0,...,n} and |w-x|+|x-y|+|y-w| <= w+x+y. A213487

Sum of the legs of the unique primitive Pythagorean triple whose inradius is the n-th prime and whose short leg is an odd number. A382097

a(n) = 676·n - 1. A158393