Properties of the Number 21382

Twenty-One Thousand Three Hundred Eighty-Two

Basics

Value: 21381 → 21382 → 21383

Parity: even

Prime: No

Previous Prime: 21379

Next Prime: 21383

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 × 10691

Divisors: 1, 2, 10691, 21382

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001110000110

Octal: 51606

Duodecimal: 1045A

Hexadecimal: 5386

Square: 457189924

Square Root: 146.22585270737866

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

Triangular array read by rows. T(n,k) is the number of sets of exactly k distinct binary words with a total of n letters. A208741

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 94 ones. A31862

Number of nX3 0..1 arrays with exactly floor(nX3/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..1 order. A222504

T(n,k)=Number of nXk 0..1 arrays with exactly floor(nXk/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..1 order. A222509

a(1) = 1, a(2) = 2, for a(n) > 2, a(n) is the smallest unused positive number that shares a factor with a(n-1) such that the exponents of each distinct prime factor of a(n-1) differ by one from those of the same prime factors of a(n). A379441

Decimal expansion of 1/378. A21382