Properties of the Number 21944

Twenty-One Thousand Nine Hundred Forty-Four

Basics

Value: 21943 → 21944 → 21945

Parity: even

Prime: No

Previous Prime: 21943

Next Prime: 21961

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 2 ³ × 13 × 211

Divisors: 1, 2, 4, 8, 13, 26, 52, 104, 211, 422

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010110111000

Octal: 52670

Duodecimal: 10848

Hexadecimal: 55b8

Square: 481539136

Square Root: 148.13507349712964

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

Numbers k such that both k and k+1 are abundant. A96399

a(n) = ∑_k=1..n floor(n/k) * 4^k-1. A344815

Numbers k such that both k and k+1 are bi-unitary abundant numbers. A318167

Numbers k such that both k and k+1 are infinitary abundant numbers (A129656). A327635

Number of balanced reduced multisystems of weight n and maximum depth whose atoms cover an initial interval of positive integers. A330676

G.f. A(x) satisfies: A(x - x·A(x)) = x + 3·x*A(x). A291819

Numbers k such that both σ(k) >= 2·k-1 and σ(k+1) >= 2*(k+1)-1. A103289

Irregular triangle read by rows: T(n, k) is the number of 2n-step closed walks on the square lattice having algebraic area k; n >= 0, 0 <= k <= floor(n²/4). A352838

Positions of squares in A276573. A277014

Numbers k such that both k and k+1 are Zumkeller numbers (A083207). A328327