Properties of the Number 21026

Twenty-One Thousand Twenty-Six

Basics

Value: 21025 → 21026 → 21027

Parity: even

Prime: No

Previous Prime: 21023

Next Prime: 21031

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 2 × 10513

Divisors: 1, 2, 10513, 21026

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101001000100010

Octal: 51042

Duodecimal: 10202

Hexadecimal: 5222

Square: 442092676

Square Root: 145.00344823486094

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

Triangle read by rows: T(n,k) = 1 + (A022166(n,k) - binomial(n,k))². A174918

Semiprimes which are the sum of three distinct positive cubes in two or more distinct ways. A180089

Values of n such that A080221(n)=6; i.e., values of n such that n is divisible by the sum of digits of n when expressed in exactly 6 of the bases b=1...n. A271311

a(n) = 841·n + 1. A158404

a(n) = (n²+1)²+1. A178390

Number of walks within N² (the first quadrant of Z²) starting and ending at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 0), (-1, 1), (0, -1), (1, 0)}. A151348

Number of length 5+2 0..n arrays with every three consecutive terms having the sum of some two elements equal to twice the third. A248438

Multiplicity of highest weight (or singular) vectors associated with character chi₅₀ of Monster module. A34438

Expansion of -x·log'(-sqrt(12·x+2·sqrt(1-4·x)+2)/4+sqrt(1-4·x)/4+5/4). A239230

A digitized pure tuning tone, sampled at standard settings for consumer audio: a(n) = floor(sin(2*π*(440/44100)*n)*32767). A320277