Properties of the Number 61821

Sixty-One Thousand Eight Hundred Twenty-One

Basics

Value: 61820 → 61821 → 61822

Parity: odd

Prime: No

Previous Prime: 61819

Next Prime: 61837

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 6869

Divisors: 1, 3, 9, 6869, 20607, 61821

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1111000101111101

Octal: 170575

Duodecimal: 2B939

Hexadecimal: f17d

Square: 3821836041

Square Root: 248.63829149992162

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

Sum of all terms on the two principal diagonals of a 2n+1 X 2n+1 square spiral. A114254

Numbers k such that (47·10^k + 403)/9 is prime. A285570

G.f. satisfies: [x^n-1] A(x)^n² = (n!)² for n>=1. A263190

Multiples of 5 containing only digits 0,...,5. A61821