Properties of the Number 21563

Twenty-One Thousand Five Hundred Sixty-Three

Basics

Value: 21562 → 21563 → 21564

Parity: odd

Prime: Yes

Previous Prime: 21559

Next Prime: 21569

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 21563

Divisors: 1, 21563

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101010000111011

Octal: 52073

Duodecimal: 1058B

Hexadecimal: 543b

Square: 464962969

Square Root: 146.84345405907612

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 the form k² + prime(k). A184935

Primes p that remain prime through at least 2 iterations of the function f(p) = p² + 4. A116886

Supersafe primes. A181841

Smallest of three consecutive primes in arithmetic progression with common difference 24 and digit sum prime. A253140

Primes of the form A108656(n-2)*n²+A108656(n-1)*n+A108656(n). A108657

Primes congruent to 28 mod 59. A142755

Primes p such that p - d and p + d are also primes, where d is the largest digit of p. A245877

Third term of weak prime sextet: p(m-1)-p(m-2) < p(m)-p(m-1) < p(m+1)-p(m) < p(m+2)-p(m+1) < p(m+3)-p(m+2). A54830

Numbers k such that (138^k + 137^k)/275 is prime. A227173

Primes p such that the base-10 concatenations (p+1)||p and (p+1)||(p+1)||p are both prime. A309749