Properties of the Number -1641

Six Hundred Forty-One

Basics

Value: -1642 → -1641 → -1640

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 3 × 547

Divisors: 1, 3, 547, 1641

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11001101001

Octal: -3151

Duodecimal: -B49

Hexadecimal: -669

Square: 2692881

Square Root: 40.50925820105819

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

Years in which a transit of Venus (as seen from Earth) took place or is expected to occur, according to the catalog by Fred Espenak. A171467

Coefficients in the expansion of ([s] + [2s]x + [3s]x² + ...)/([r] + [2r]x + [3r]x² + ...); [ ] = floor, r = sqrt(2), s = sqrt(3). A279628

Expansion of -1/(1 - x + x² - x³ + x⁴ + x⁶). A125629

Values of n such that L(15) and N(15) are both prime, where L(k) = (n²+n+1)*2^2·k + (2·n+1)*2^k + 1, N(k) = (n²+n+1)*2^k + n. A227518

Dirichlet g.f.: ζ(s-1) / (ζ(s) * ζ(s-2)). A328502

Central polygonal numbers: a(n) = n² - n + 1. A2061

Coordination sequence T1 for Zeolite Code LTA and ρ. A8137

a(n) = ∑_k=1..n n/gcd(n,k). A57660

a(n) = 4·n² - 6·n + 3. A54569

a(n) = least m such that if a/b < c/d where a,b,c,d are integers in [0,n], then a/b < k/m < c/d for some integer k. A1000