Properties of the Number -1915

Nine Hundred Fifteen

Basics

Value: -1916 → -1915 → -1914

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 5 × 383

Divisors: 1, 5, 383, 1915

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11101111011

Octal: -3573

Duodecimal: -1137

Hexadecimal: -77b

Square: 3667225

Square Root: 43.76071297408213

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

Reflected tetranacci numbers A073817. A74058

Triangle of coefficients of p(x,n) = (1-x)ⁿ⁺¹*∑_{m >= 0} ((3·m+2)ⁿ - (3·m+1)ⁿ)*x^m, read by rows. A154853

Expansion of ∏_m>=1 (1 - m·q^m)². A22662

a(1) = 1; a(n+1) = a(n) +- (sum of digits of a(1) up to a(n)), with "+" when a(n) is odd, or "-" if even. A332058

Matrix inverse of A008278, which is the reflected triangle of the Stirling numbers of 2nd kind. A106342

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 437", based on the 5-celled von Neumann neighborhood. A272156

G.f. satisfies: [xⁿ] A(x)⁽ⁿ⁺¹²) = (n+1)² for n>=1; that is, the coefficient of xⁿ in the (n+1)² power of g.f. A(x) equals (n+1)². A172440

a(n) = 4·n² - 9·n + 6. A54556

Number of nonisomorphic semigroups of order n. A27851

a(n) = 2·a(n-1) - 2·a(n-3) + a(n-4) for n > 3, with initial terms 1, 1, 4, 8. A267682