Properties of the Number 17991

Seventeen Thousand Nine Hundred Ninety-One

Basics

Value: 17990 → 17991 → 17992

Parity: odd

Prime: No

Previous Prime: 17989

Next Prime: 18013

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 1999

Divisors: 1, 3, 9, 1999, 5997, 17991

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100011001000111

Octal: 43107

Duodecimal: A4B3

Hexadecimal: 4647

Square: 323676081

Square Root: 134.13053343664893

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

Padovan sequence (or Padovan numbers): a(n) = a(n-2) + a(n-3) with a(0) = 1, a(1) = a(2) = 0. A931

a(0) = 0, a(1) = a(2) = a(3) = 1; thereafter, a(n) = a(n-1) + a(n-2) + a(n-4). A5251

Number of n-th generation triangles in the tiling of the hyperbolic plane by triangles with angles {π/2, π/3, 0}. A96231

Expansion of 1/(1-x²-x³). A182097

Padovan's spiral numbers. A134816

Spiral of triangles around a hexagon. A164001

Expansion of (1 - x)/(1 - x² - x³). A78027

Expansion of (1+x)/(1-x²+x³). A124745

The number of all possible covers of L-length line segment by 2-length line segments with allowed gaps < 2. A228361

Expansion of (1 - x)/(1 - 3·x + 2·x² - x³). A52921