Properties of the Number -91000

Ninety-One Thousand

Basics

Value: -91001 → -91000 → -90999

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 2 ³ × 5 ³ × 7 × 13

Divisors: 1, 2, 4, 5, 7, 8, 10, 13, 14, 20

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10110001101111000

Octal: -261570

Duodecimal: -447B4

Hexadecimal: -16378

Square: 8281000000

Square Root: 301.66206257996714

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

a(0)=a(1)=1, a(n) = least k > a(n-1) such that k·a(n-2) is a triangular number. A214961

G.f.: ∑_n>=0 (xⁿ - 1)ⁿ * xⁿ / (1-x)ⁿ⁺¹. A243919

Numbers n with property that n and 2n are sums of two distinct positive cubes. A191345

Sum of two (possibly negative) cubes in at least 3 ways. A51383

Numbers k such that squarefree part of σ(k) is equal to squarefree part of 2·k. A331752

Inflation orbit counts b⁽³⁾_n for Danzer's F-type tiling and other 3D cut and project patterns with τ-inflation. A324488

The Wiener index of the zig-zag polyhex nanotube TUHC₆[2n,2] defined pictorially in Fig. 1 of the Eliasi et al. reference. A227703

Numbers k such that (k, φ(k), σ(k)) lies on a sphere with integral radius centered at the origin, i.e., k² + φ(k)² + σ(k)² is a square. A66785

Numbers k such that σ(k)*φ(k)*k is a square. A114079

Expansion of 1 / ((1+x)*(1-x-4·x²)). (5,4)-Padovan sequence. A176738