Properties of the Number 21212

Twenty-One Thousand Two Hundred Twelve

Basics

Value: 21211 → 21212 → 21213

Parity: even

Prime: No

Previous Prime: 21211

Next Prime: 21221

Digit Sum: 8

Digital Root: 8

Palindrome: Yes

Factorization: 2 ² × 5303

Divisors: 1, 2, 4, 5303, 10606, 21212

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101001011011100

Octal: 51334

Duodecimal: 10338

Hexadecimal: 52dc

Square: 449948944

Square Root: 145.64340012510007

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

Palindromes in base 3 (written in base 3). A118594

List of primitive words over the alphabet {1,2}. A213969

The Wythoff representation of n: an alternative way of presenting A189921. A317208

Palindromic and divisible by 4. A45639

a(n) is the smallest number not already present that permits the cyclic repetition of the path 1,2 of the digits in the sequence. A165300

Numbers with digits in {0,1,2} such that every other digit is strictly less than its neighbors. A306105

Two-bell analog of A028355. A28359

Base-2 digital convolution sequence. A33639

Base-10 palindromes that start with 2. A43037

G.f. A(x) satisfies: A( 4·A(x)⁴ - 64·A(x)⁵ ) = 4·x⁴. A369534