Properties of the Number 71821

Seventy-One Thousand Eight Hundred Twenty-One

Basics

Value: 71820 → 71821 → 71822

Parity: odd

Prime: Yes

Previous Prime: 71809

Next Prime: 71837

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 71821

Divisors: 1, 71821

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10001100010001101

Octal: 214215

Duodecimal: 35691

Hexadecimal: 1188d

Square: 5158256041

Square Root: 267.9944029266283

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

Prime hypotenuses of Pythagorean triangles with a prime leg. A67756

Greatest prime factor of n⁷+1. A240550

Value of prime number D for incrementally largest values of minimal·satisfying the equation x² - D·y² = -3. A336801

Primes of the form (4·k + 1)² + (4·k + 2)² where k=0,1,2,3,... A87871

Primes that can be generated by the concatenation in base 8, in ascending order, of two consecutive integers read in base 10. A287310

Value of prime number D for incrementally largest values of minimal y satisfying the equation x² - D·y² = -3. A341077

Numbers k such that d(k) < d(k+1) < d(k+2) < d(k+3) < d(k+4), where d(n) is the number of divisors of n. A364717

Numbers having exactly four anti-divisors. A66469

Primes of the form (p^k + k - 1)/k for prime p and some k > 1. A230444

Primes of the form (p^k+1)/2 where p is prime and k > 1. A308442