Properties of the Number 80921

Eighty Thousand Nine Hundred Twenty-One

Basics

Value: 80920 → 80921 → 80922

Parity: odd

Prime: No

Previous Prime: 80917

Next Prime: 80923

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 19 × 4259

Divisors: 1, 19, 4259, 80921

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10011110000011001

Octal: 236031

Duodecimal: 3A9B5

Hexadecimal: 13c19

Square: 6548208241

Square Root: 284.46616670528675

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 nodes in regular n-gon with all diagonals drawn. A7569

a(1) = 1, then multiply, add and subtract 2, 3, 4; 5, 6, 7; ... in that order. A77382

a(n) = 70·n² + 1. A158734

Table read by antidiagonals: Place k equally spaced points on each side of a regular n-gon and join every pair of the n*(k+1) boundary points by a chord; T(n,k) (n >= 3, k >= 0) gives the number of vertices in the resulting planar graph. A367322

a(n) = 2·a(n-1) + 48·a(n-2), a(0)=0, a(1)=1. A80921

E.g.f. satisfies: A(x) = ∑_n>=0 xⁿ/n! * ∏_k=1..n A(k·x)^1/k. A230318