Properties of the Number 21395

Twenty-One Thousand Three Hundred Ninety-Five

Basics

Value: 21394 → 21395 → 21396

Parity: odd

Prime: No

Previous Prime: 21391

Next Prime: 21397

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 5 × 11 × 389

Divisors: 1, 5, 11, 55, 389, 1945, 4279, 21395

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001110010011

Octal: 51623

Duodecimal: 1046B

Hexadecimal: 5393

Square: 457746025

Square Root: 146.27029773675858

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

Convolution of A000203 with itself. A385

Number of ordered octuples of distinct pairwise coprime positive integers with largest element n. A186979

Number of 7-element subsets of {1, 2, ..., n} having pairwise coprime elements. A186983

Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any horizontal, vertical or antidiagonal neighbor, and containing the value n(n+1)/2-2. A211924

Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1)², where a(0) = 3, a(1) = 4, b(0) = 1, b(1) = 2, and (a(n)) and (b(n)) are increasing complementary sequences. A296256

Number of 2 X 2 matrices having all terms in {1,...,n} and determinant d satisfying -n < d < n. A211070

1 + n-th prime is harmonic. A74692

Number of walks within N³ (the first octant of Z³) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (0, 1, 1), (1, -1, 0), (1, -1, 1), (1, 1, -1)}. A149492

Decimal expansion of 1/391. A21395