Properties of the Number -2187

One Hundred Eighty-Seven

Basics

Value: -2188 → -2187 → -2186

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ⁷

Divisors: 1, 3, 9, 27, 81, 243, 729, 2187

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -100010001011

Octal: -4213

Duodecimal: -1323

Hexadecimal: -88b

Square: 4782969

Square Root: 46.76537180435969

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: Yes

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: coefficients T(n,k) of a binomial decomposition of 2ⁿ-1 as Sum(k=0..n)T(n,k)*binomial(n,k). A244124

Expansion of bracket function. A748

a(n) = ∑_{j=0..floor(n/3)} (-1)^j*binomial(n,3·j). A57681

Inverse binomial transform of A140962. A141413

Triangle T, read by rows, where matrix power T³ has powers of 3 in the secondary diagonal: [T³](n+1,n) = 3ⁿ⁺¹, with all 1's in the main diagonal and zeros elsewhere. A117252

a(n) = A166405(n)-A166100(n). A166406

G.f. A(x) satisfies A(x) = A(x)⁴ - 9·x. A247029

Expansion of (1 - 3x)/(1 + 3·x²). A128019

G.f.: A(x) = 1 + x/exp( ∑_k>=1 (A((-1)^k*x) - 1)^k/k ). A157674

Triangle, read by rows, where the n-th row lists the (2·n+1) coefficients of (1 + x - 3·x²)ⁿ. A84614