Properties of the Number 21826

Twenty-One Thousand Eight Hundred Twenty-Six

Basics

Value: 21825 → 21826 → 21827

Parity: even

Prime: No

Previous Prime: 21821

Next Prime: 21839

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 × 7 × 1559

Divisors: 1, 2, 7, 14, 1559, 3118, 10913, 21826

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010101000010

Octal: 52502

Duodecimal: 1076A

Hexadecimal: 5542

Square: 476374276

Square Root: 147.7362514753911

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 that can be partitioned into a set of sets. A382077

T(n,k)=Number of nXk 0..4 arrays with each element·equal to the number of its horizontal and vertical neighbors equal to 3,2,1,4,0 for x=0,1,2,3,4. A197167

a(n) = A276086(n)*A276086(σ(n)-n) - A276086(σ(n)), where A276086 is the primorial base exp-function, and σ is the sum of divisors function. A388281

Square excess of Fibonacci numbers. A190993

Numbers k such that k divides the (right) concatenation of all numbers <= k written in base 22 (most significant digit on right). A29515

Even composites in A145832 with at least three distinct prime factors. A145916

Number of binary strings of length n+10 such that the smallest number whose binary representation is not visible in the string is 10. A261475

XOR difference triangle of the powers of 3, read by rows. A99887

Number of nX4 0..4 arrays with each element·equal to the number its horizontal and vertical neighbors equal to 3,2,1,4,0 for x=0,1,2,3,4. A197163

Number of nX5 0..4 arrays with each element·equal to the number its horizontal and vertical neighbors equal to 3,2,1,4,0 for x=0,1,2,3,4. A197164