Properties of the Number 21799

Twenty-One Thousand Seven Hundred Ninety-Nine

Basics

Value: 21798 → 21799 → 21800

Parity: odd

Prime: Yes

Previous Prime: 21787

Next Prime: 21803

Digit Sum: 28

Digital Root: 1

Palindrome: No

Factorization: 21799

Divisors: 1, 21799

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010100100111

Octal: 52447

Duodecimal: 10747

Hexadecimal: 5527

Square: 475196401

Square Root: 147.64484413619056

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

Smaller member of a pair (p,q) of cousin primes such that p and q are in different centuries. A160440

Primes p such that x³⁶ = 2 has no solution mod p, but x¹² = 2 has a solution mod p. A59668

Primes p such that both (p² + 5)/6 and (p⁴ + 5)/6 are prime. A253925

Number of compositions (ordered partitions) of n into at most 6 nonprime parts. A347799

a(n) is the least number such that d(a(n)) = d(R(a(n)))/n, where R(n) is the digit reverse of n and d(n) is the number of divisors of n. A284495

Positive-pan primes (see Comments). A332788

Primes congruent to 28 mod 59. A142755

G.f. A(x) satisfies A(x) = 1 - x/A(x)² * (1 - A(x) - A(x)³). A371889

a(1) = 2 then primes in nondecreasing order such that every concatenation is prime. A89702

Primes p such that 2·p³-+15 are also prime. A174364