Properties of the Number 21858

Twenty-One Thousand Eight Hundred Fifty-Eight

Basics

Value: 21857 → 21858 → 21859

Parity: even

Prime: No

Previous Prime: 21851

Next Prime: 21859

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 2 × 3 × 3643

Divisors: 1, 2, 3, 6, 3643, 7286, 10929, 21858

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010101100010

Octal: 52542

Duodecimal: 10796

Hexadecimal: 5562

Square: 477772164

Square Root: 147.844512918133

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

Number of integer partitions of n with an alternating permutation. A345170

Number of integer partitions of n with a permutation that has no consecutive monotone triple, i.e., no triple (..., x, y, z, ...) such that either x <= y <= z or x >= y >= z. A344740

Table read by antidiagonals: T(m,n) = number of (m-2)-metered (m,n)-parking functions. A372821

Table read by antidiagonals: T(t,n) = number of t-metered parking functions of length n. A372816

Table read by antidiagonals: T(m,n) = number of 4-metered (m,n)-parking functions. A372820

a(n) is the number of 5 element sets of distinct integer-sided trapezoids whose base angles are 60 degrees that fill an equilateral triangular grid of side n units with a trapezoid filled by 3 trapezoids. A391204

Expansion of 1/sqrt((1 - x + x⁴)² + 4·x⁵). A375293

Number of achiral planar maps with n vertices and 2 faces. A380238

Number of n-node rooted trees of height 10. A245068

Numbers m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,39. A64256