Properties of the Number 21970

Twenty-One Thousand Nine Hundred Seventy

Basics

Value: 21969 → 21970 → 21971

Parity: even

Prime: No

Previous Prime: 21961

Next Prime: 21977

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 × 5 × 13 ³

Divisors: 1, 2, 5, 10, 13, 26, 65, 130, 169, 338

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010111010010

Octal: 52722

Duodecimal: 1086A

Hexadecimal: 55d2

Square: 482680900

Square Root: 148.22280526288793

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

Number of compositions of n avoiding three consecutive parts in arithmetic progression. A238423

Numbers of the form (10ⁱ)*(13^j), with i, j >= 0. A108761

Triangle read by rows: T(i,j) is the number of i-permutations of 14 objects a,b,c,d,e,f,g,h,i,j,k,l,m,n, with repetition allowed, containing j a's. A133371

a(n) = 10·n³. A244729

Consider primitive pairs of integers (b, c) with b > 0 such that x⁵ + b·x + c = 0 is irreducible and solvable by radicals: sequence gives values of b. A371553

Nonsquarefree numbers k such that A003415(k) divides A276086(k), where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function. A371085

Numbers m such that σ(σ(m))/m is a square. A318084

Numbers k such that the continued fraction for sqrt(k) has period 61. A20400

Triangle of coefficients in expansion of (1+13x)ⁿ. A123187

Numbers k with equal remainders of (product of divisors of k) mod (sum of divisors of k) and (product of proper divisors of k) mod (sum of proper divisors of k). A192035