Properties of the Number -987

Nine Hundred Eighty-Seven

Basics

Value: -988 → -987 → -986

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 7 × 47

Divisors: 1, 3, 7, 21, 47, 141, 329, 987

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -1111011011

Octal: -1733

Duodecimal: -6A3

Hexadecimal: -3db

Square: 974169

Square Root: 31.416556144810016

Classification

Fibonacci: Yes

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(n+2) = -a(n+1) + a(n) (signed Fibonacci numbers) with a(-2) = a(-1) = 1; or Fibonacci numbers (A000045) extended to negative indices. A39834

Triangle of Lehmer-Comtet numbers of the first kind. A8296

a(n) = a(n-1)+a(n-2), n>1 ; a(0)=1, a(1)=-1. A152163

Triangle of coefficients of Chebyshev's S(n,x-3) polynomials (exponents of·in increasing order). A207815

Expansion of (1-x)*(1-x+x²)/(1-3·x+4·x²-2·x³+x⁴). A105371

a(n) = (-1)^n-1*(a(n-1) - a(n-2)), a(1)=1, a(2)=1. A51792

A transform of the Fibonacci numbers. A103311

Triangle read by rows. The matrix inverse of A354794. Equivalently, the Bell transform of cfact(n) = -(n - 1)! if n > 0 and otherwise 1/(-n)!. A354795

a(1) = 0, a(2) = -2; for n > 2, a(n) + a(n-2) - a(n-3) - a(n-5) - ... - a(n-p) = (-1)ⁿ⁺¹*n if n is prime, otherwise = 0, where p = largest prime < n. A2120

G.f.: A(x) = ∑_n=-oo..+oo (x - xⁿ)ⁿ. A290003