Properties of the Number -1919

Nine Hundred Nineteen

Basics

Value: -1920 → -1919 → -1918

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 19 × 101

Divisors: 1, 19, 101, 1919

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11101111111

Octal: -3577

Duodecimal: -113B

Hexadecimal: -77f

Square: 3682561

Square Root: 43.80639222761902

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

Numerators of the rational number triangle R(n, k) = (n⁴ - 30·n²*k² + 60·n*k³ -30·k⁴) / (120·n), n >= 1, k = 1, ..., n. This is a regularized ∑_{j >= 0} (k + n·j)^-s for s = -3 defined by analytic continuation of a generalized Hurwitz ζ function. A268919

a(n) = ∑_k=0..n A105595(k)*(-1)^k*A105595(n-k) (interpolated zeros suppressed). A105596

A sixth-order linear divisibility sequence: a(n+6) = -3·a(n+5) - 5·a(n+4) - 5·a(n+3) - 5·a(n+2) - 3·a(n+1) - a(n). A5120

Values of n such that L(16) and N(16) 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. A227519

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 361", based on the 5-celled von Neumann neighborhood. A271417

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 387", based on the 5-celled von Neumann neighborhood. A271546

Expansion of e.g.f. ∏_k>=1 (1 + x^k)^(-1^(k+1)/k). A295834

A symmetrical triangular sequence:t(n,m)=n!*(StirlingS1[n, m] + StirlingS1[n, n - m] - (StirlingS1[n, 0] + StirlingS1[n, n]) + 1) - n! + 1. A174861

Number of subsets {x(1),x(2),...,x(k)} of {1,2,...,n} such that all differences |x(i)-x(j)| are distinct. A143823

Triangle, read by rows of n²+1 terms, of coefficients of q in the q-analog of the even double factorials: T(n,k) = [q^k] ∏_j=1..n (1-q^2j)/(1-q) for n>0, with T(0,0)=1. A128084