Properties of the Number 21613

Twenty-One Thousand Six Hundred Thirteen

Basics

Value: 21612 → 21613 → 21614

Parity: odd

Prime: Yes

Previous Prime: 21611

Next Prime: 21617

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 21613

Divisors: 1, 21613

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010001101101

Octal: 52155

Duodecimal: 10611

Hexadecimal: 546d

Square: 467121769

Square Root: 147.0136048126159

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

Primes of form k² + 4. A5473

Primes p for which the period of reciprocal 1/p is (p-1)/12. A56217

Greater of twin primes of the form x²+2, x²+4. A85554

Let F(g,p) be the frequency of g up to prime nextprime(p+1). Primes p such that F(2,p) = F(4,p) and g = 2 or 4. A274122

Primes of the form n² + 4n + 8. A98062

Primes with 4 distinct digits that remain prime (no leading zeros allowed) after deleting all occurrences of its digits d. A57880

Primes p containing the string "13" and sum of digits sod(p) = 13. A175017

Sequence of primes separated by [sequence of prime] elements. 2, [find 2nd prime after 2 = ] 5, [find 3rd prime after 5 =] 13, [find 5th prime after 13 =] 61, ..., etc. A180302

Primes whose sum of reciprocal of digits is a prime. A266815

Numbers k such that φ(k) > φ(k+1) > φ(k+2) > φ(k+3) where φ is the Euler totient function (A000010). A326817