Properties of the Number 21097

Twenty-One Thousand Ninety-Seven

Basics

Value: 21096 → 21097 → 21098

Parity: odd

Prime: No

Previous Prime: 21089

Next Prime: 21101

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 17 ² × 73

Divisors: 1, 17, 73, 289, 1241, 21097

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001001101001

Octal: 51151

Duodecimal: 10261

Hexadecimal: 5269

Square: 445083409

Square Root: 145.24806367039804

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) = n²*(n²+3)/4. A39623

Composite numbers for which A324644(n)/A324198(n) = 2 and σ(n) == 2 (mod 4). A371082

Odd 10-gonal (or decagonal) numbers. A28993

The location of records in A210700. A210701

On a spirally numbered square grid, with labels starting at 1, this is the number of the last cell that an (n,n+1) leaper reaches before getting trapped, or -1 if it never gets trapped. A343179

Numbers k such that the k-th triangular number contains only digits {2,3,5}. A119153

Series reversion of the g.f. of A228862. A228863

Strong pseudoprimes to base 38. A20264

Floor of sum of the first 10ⁿ square roots. A137262

a(n) = 73·n². A174334