Properties of the Number -1387

Three Hundred Eighty-Seven

Basics

Value: -1388 → -1387 → -1386

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 19 × 73

Divisors: 1, 19, 73, 1387

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10101101011

Octal: -2553

Duodecimal: -977

Hexadecimal: -56b

Square: 1923769

Square Root: 37.242448899072144

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

Matrix inverse of triangle A121335, where A121335(n,k) = C( n*(n+1)/2 + n-k + 1, n-k) for n>=k>=0. A121440

a(n) = ∑_{k=0..floor(n/2)} binomial(n - k*(k-1)/2, k). A64188

The main diagonal of the array of A141425 and its higher order differences. A141516

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 433", based on the 5-celled von Neumann neighborhood. A272148

Fermat pseudoprimes to base 2, also called Sarrus numbers or Poulet numbers. A1567

Hex (or centered hexagonal) numbers: 3·n*(n+1)+1 (crystal ball sequence for hexagonal lattice). A3215

10-gonal (or decagonal) numbers: a(n) = n*(4·n-3). A1107

Generalized 10-gonal numbers: m*(4·m - 3) for m = 0, +- 1, +- 2, +- 3, ... A74377

Partial sums of A299254. A299260

Expansion of g.f. x*(1 + 3·x)/((1 + x)*(1 - x)³). A35608