Properties of the Number 21895

Twenty-One Thousand Eight Hundred Ninety-Five

Basics

Value: 21894 → 21895 → 21896

Parity: odd

Prime: No

Previous Prime: 21893

Next Prime: 21911

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 5 × 29 × 151

Divisors: 1, 5, 29, 145, 151, 755, 4379, 21895

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010110000111

Octal: 52607

Duodecimal: 10807

Hexadecimal: 5587

Square: 479391025

Square Root: 147.96959147068023

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

Irregular triangle read by rows: T(n,k) gives the number of ballot sequences of length n having k descents, n>=0, 0<=k<=A083920(n-1). A238122

a(n) = (8·n+1)*(8·n+7). A1533

Perimeter of integer triangle (A001611(n), A001611(n+1), A001611(n+2)). A97280

Number of (w,x,y,z) with all terms in {0,...,n} and w=max{w,x,y,z}-2·min{w,x,y,z}. A212745

Number of ballot sequences of length n having exactly six descents. A241799

Number of ballot sequences of length 2n+1 having exactly n descents. A241805

a(n) = (n + 2)*(n² + n - 1). A318765

a(n) = (6·n+1)*(6·n+7). A85026

a(n) = the n-bit number in which the i-th bit is 1 if and only if prime(i) divides A060795(n). A277428

Triangle read by rows: T(n,k) gives the number of ballot sequences of length n having exactly k descents, n>=0, 0<=k<=n. A238121