Properties of the Number 1387

One Thousand Three Hundred Eighty-Seven

Basics

Value: 1386 → 1387 → 1388

Parity: odd

Prime: No

Previous Prime: 1381

Next Prime: 1399

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

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

Discriminants of imaginary quadratic fields with class number 4 (negated). A13658

The number of n-full sets, F(n). A188431

"Three-quarter squares": a(n) = n² - A002620(n). A77043

Number of (necessarily strict) integer partitions of n with no two consecutive parts divisible. A328171