Properties of the Number 12921

Twelve Thousand Nine Hundred Twenty-One

Basics

Value: 12920 → 12921 → 12922

Parity: odd

Prime: No

Previous Prime: 12919

Next Prime: 12923

Digit Sum: 15

Digital Root: 6

Palindrome: Yes

Factorization: 3 × 59 × 73

Divisors: 1, 3, 59, 73, 177, 219, 4307, 12921

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 11001001111001

Octal: 31171

Duodecimal: 7589

Hexadecimal: 3279

Square: 166952241

Square Root: 113.67057666784312

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

Nonnegative values·of solutions (x, y) to the Diophantine equation x²+(x+79)² = y². A118676

Consider all (2n+1)-digit palindromic primes of the form 10...0M0...01 (so that M is a palindrome with <= 2n-1 digits); a(n) = smallest such M. A100026

G.f.: ∑_k>=0 x^k * ∏_j=1..4·k (1 + x^j). A385068

Partial sums of ∑_k=1..n n/gcd(n,k), or partial sums of ∑_d∣n d*φ(d) (see A057660). A174405

Partial sums of usigma(n)²: square of the sum of unitary divisors of n. A74789

Odd palindromes in which parity of digits alternates. A30148

Palindromes n such that 10n01 is a prime. A99744

Palindromic mountain numbers. A173070

Palindromic nonprime numbers starting with a digit 1. A222724

Palindromic odd composite numbers that are the products of an odd number of distinct primes. A75808