Properties of the Number -1391

Three Hundred Ninety-One

Basics

Value: -1392 → -1391 → -1390

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 13 × 107

Divisors: 1, 13, 107, 1391

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10101101111

Octal: -2557

Duodecimal: -97B

Hexadecimal: -56f

Square: 1934881

Square Root: 37.296112397943034

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

Coefficients in the expansion of 1/([r] + [2r]x + [3r]x² + ...); [ ] = floor, r = 6/5. A279778

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 405", based on the 5-celled von Neumann neighborhood. A271815

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 467", based on the 5-celled von Neumann neighborhood. A272321

a(n) = floor(-(3/2)*a(n-1)), a(1)=-2. A333588

Number of elements in the set {(x,y): 1 <= x,y <= n, gcd(x,y)=1}. A18805

G.f.: ∏_j>=1 ∏_i>=1 (1 + x^i·j). A107742

Numbers k such that the k-th Euclid number A006862(k) = 1 + (Product of first k primes) is prime. A14545

Multiples of 13 containing a 13 in their decimal representation. A121033

Mountain numbers. A134941

Number of integer partitions of n that can be partitioned into sets with distinct sums. A381992