Properties of the Number 81009

Eighty-One Thousand Nine

Basics

Value: 81008 → 81009 → 81010

Parity: odd

Prime: No

Previous Prime: 81001

Next Prime: 81013

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 9001

Divisors: 1, 3, 9, 9001, 27003, 81009

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011110001110001

Octal: 236161

Duodecimal: 3AA69

Hexadecimal: 13c71

Square: 6562458081

Square Root: 284.62080036427415

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 (n+1)X(k+1) 0..1 arrays with rows and columns of determinants of all 2X2 subblocks lexicographically nondecreasing. A204800

Number of (n+1) X 3 0..1 arrays with rows and columns of determinants of all 2 X 2 subblocks lexicographically nondecreasing. A204794

Number of (n+1)X7 0..1 arrays with rows and columns of determinants of all 2X2 subblocks lexicographically nondecreasing. A204798

Array read by downward antidiagonals: A(n,k) = (k+2)*A(n-1,k+1) + ∑_j=0..k A(n-1,j) with A(0,k) = 1, n >= 0, k >= 0. A370380

a(n) = Fibonacci(4n+3) - 1, or Fibonacci(2n+2)*Lucas(2n+1). A81009