Properties of the Number 1381

One Thousand Three Hundred Eighty-One

Basics

Value: 1380 → 1381 → 1382

Parity: odd

Prime: Yes

Previous Prime: 1373

Next Prime: 1399

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 1381

Divisors: 1, 1381

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10101100101

Octal: 2545

Duodecimal: 971

Hexadecimal: 565

Square: 1907161

Square Root: 37.16180835212409

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

Primes p such that (p+1)/2 is prime. A5383

Number of "ON" cells at n-th stage in the "Ulam-Warburton" two-dimensional cellular automaton. A147562

Centered pentagonal numbers: (5n²+5n+2)/2; crystal ball sequence for 3.3.3.4.4. planar net. A5891

Y-toothpick sequence (see Comments lines for definition). A160120

Primes such that their decimal representations interpreted in base 11 are also prime. A91924

Primes of the form 2·k² + 29. A7641

Primes congruent to 1 or 19 (mod 30). A33212

Primes of the form 4·x²+x·y-4·y² (as well as of the form 4·x²+9·x*y+y²). A141111

Primes that are the sum of three consecutive primes. A34962

Primes of the form x² + 45y². A107152