Properties of the Number 81684

Eighty-One Thousand Six Hundred Eighty-Four

Basics

Value: 81683 → 81684 → 81685

Parity: even

Prime: No

Previous Prime: 81677

Next Prime: 81689

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 2 ² × 3 ² × 2269

Divisors: 1, 2, 3, 4, 6, 9, 12, 18, 36, 2269

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 10011111100010100

Octal: 237424

Duodecimal: 3B330

Hexadecimal: 13f14

Square: 6672275856

Square Root: 285.80412873154927

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

Triangle read by rows: T(n,k)=number of ordered trees with n edges and k branch nodes at odd height. A91958

Triangle T, read by rows : T(n,k) = A007318(n,k)*A026641(n-k). A171650

G.f. satisfies: A(x/A(x)) = 1 + sqrt(x - x/A(x)). A185753

a(n) = 5ⁿ - 4ⁿ - 3ⁿ - 2ⁿ + 3. A81684