Properties of the Number 81291

Eighty-One Thousand Two Hundred Ninety-One

Basics

Value: 81290 → 81291 → 81292

Parity: odd

Prime: No

Previous Prime: 81283

Next Prime: 81293

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 7 ³ × 79

Divisors: 1, 3, 7, 21, 49, 79, 147, 237, 343, 553

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011110110001011

Octal: 236613

Duodecimal: 3B063

Hexadecimal: 13d8b

Square: 6608226681

Square Root: 285.11576596182823

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 integer compositions of n that are the 0-prepended first sums of some finite sequence of distinct integers. A392702

Number of different n X n symmetric matrices with nonnegative entries summing to 4. Also number of symmetric oriented graphs with 4 arcs on n points. A139594

Number of length 5 0..n arrays least squares fitting to a zero slope straight line, with a single point taken as having zero slope. A245135

Triangle read by rows: T(n,k) is the number of labeled quasi-threshold graphs on vertex set [n] with k components, for n >= 1 and 1 <= k <= n. A350528

Complement of A072795. A81291