Properties of the Number -1639

Six Hundred Thirty-Nine

Basics

Value: -1640 → -1639 → -1638

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 11 × 149

Divisors: 1, 11, 149, 1639

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11001100111

Octal: -3147

Duodecimal: -B47

Hexadecimal: -667

Square: 2686321

Square Root: 40.48456495999432

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(n) = -2·a(n-1) + 3·a(n-2), with a(0)=1, a(1)=2. A84222

Row sums of a number triangle related to the Pell numbers. A110331

Numerators of coefficients in Taylor series for exp(cos(x)-1). A47689

Logarithmic derivative of the q-exponential of x, E_q(x,q), evaluated at q=-x. A198262

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 97", based on the 5-celled von Neumann neighborhood. A270155

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 389", based on the 5-celled von Neumann neighborhood. A271597

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 401", based on the 5-celled von Neumann neighborhood. A271806

a(n) = n + (n+1)². A28387

9-gonal (or enneagonal or nonagonal) numbers: a(n) = n*(7·n-5)/2. A1106

Generalized 9-gonal (or enneagonal) numbers: m*(7·m - 5)/2 with m = 0, 1, -1, 2, -2, 3, -3, ... A118277