Properties of the Number 20087

Twenty Thousand Eighty-Seven

Basics

Value: 20086 → 20087 → 20088

Parity: odd

Prime: No

Previous Prime: 20071

Next Prime: 20089

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 53 × 379

Divisors: 1, 53, 379, 20087

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100111001110111

Octal: 47167

Duodecimal: B75B

Hexadecimal: 4e77

Square: 403487569

Square Root: 141.72861390700186

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

Odd composite integers m such that A004254(m-J(m,21)) == 0 (mod m) and gcd(m,21)=1, where J(m,21) is the Jacobi symbol. A340098

Numbers k such that 210·k+{11, 13, 17, 19, 23, 29} are 6 consecutive primes. A182282

Numerators of the convergents to log₂(5). A116985

Odd composite integers m such that U(m)² == 1 (mod m) and V(m) == 5 (mod m), where U(m)=A004254(m) and V(m)=A003501(m) are the m-th generalized Lucas and Pell-Lucas numbers of parameters a=5 and b=1, respectively. A337779

a(n) = 62·n² - 1. A158680

Numbers which are palindromic in their Elias δ code representation. A281380

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 21 ones. A31789

Numbers k such that 2^k + k³ is prime. A58015

Numbers k such that 10^k + 109 is prime. A258933

a(n) = floor( γ(n + 1/4)/γ(1/4) ). A20087