Properties of the Number 61581

Sixty-One Thousand Five Hundred Eighty-One

Basics

Value: 61580 → 61581 → 61582

Parity: odd

Prime: No

Previous Prime: 61561

Next Prime: 61583

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 13 × 1579

Divisors: 1, 3, 13, 39, 1579, 4737, 20527, 61581

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1111000010001101

Octal: 170215

Duodecimal: 2B779

Hexadecimal: f08d

Square: 3792219561

Square Root: 248.15519337704782

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

T(n,k)=Number of -k..k circular arrays x(0..n+1) of n+2 elements with zero sums of x(i) and x(i)*x((i+1) mod (n+2)). A202006

Number of -2..2 circular arrays x(0..n+1) of n+2 elements with zero sums of x(i) and x(i)*x((i+1) mod (n+2)). A202000

a(1) = 1, a(n) = number obtained by replacing each digit of a(n-1) with its double. A61581

For n >= 3, a(n) is the least r >= 0 such that the elliptic equation y² = n³ + n² + 2·r*n + r² has an integer solution. A364248