Properties of the Number 21010

Twenty-One Thousand Ten

Basics

Value: 21009 → 21010 → 21011

Parity: even

Prime: No

Previous Prime: 21001

Next Prime: 21011

Digit Sum: 4

Digital Root: 4

Palindrome: No

Factorization: 2 × 5 × 11 × 191

Divisors: 1, 2, 5, 10, 11, 22, 55, 110, 191, 382

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101001000010010

Octal: 51022

Duodecimal: 101AA

Hexadecimal: 5212

Square: 441420100

Square Root: 144.9482666333061

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

n written in fractional base 3/2. A24629

T(n,k)=Unmatched value maps: number of nXk binary arrays indicating the locations of corresponding elements not equal to any horizontal, diagonal or antidiagonal neighbor in a random 0..2 nXk array. A219002

T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 3 neighboring 1s. A297654

T(n,k) = Number of n X k binary arrays with every one adjacent to another one horizontally or vertically. A202802

T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally or vertically adjacent to 1, 2 or 3 1s. A295416

Numbers k such that k+1, k+3, k+7 and k+9 are all primes. A125855

Full Łukasiewicz word for each rooted plane tree (interpretation e in Stanley's exercise 19) encoded by A014486 (or A063171). A79436

Numbers k such that digit sum of k = number of distinct prime factors of k. A285494

a(1) = 1; a(n+1) is the smallest number > a(n) which differs from it at every digit. A68860

Number of n X 2 binary arrays with every one adjacent to another one horizontally or vertically. A202796