500809 has 2 divisors, whose sum is σ = 500810. Its totient is φ = 500808.

The previous prime is 500807. The next prime is 500831. The reversal of 500809 is 908005.

It is an a-pointer prime, because the next prime (500831) can be obtained adding 500809 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 356409 + 144400 = 597^2 + 380^2 .

It is a cyclic number.

It is not a de Polignac number, because 500809 - 2¹ = 500807 is a prime.

Together with 500807, it forms a pair of twin primes.

It is an Ulam number.

500809 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 500809.

It is not a weakly prime, because it can be changed into another prime (500807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250404 + 250405.

It is an arithmetic number, because the mean of its divisors is an integer number (250405).

2⁵⁰⁰⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

500809 is a deficient number, since it is larger than the sum of its proper divisors (1).

500809 is an equidigital number, since it uses as much as digits as its factorization.

500809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 500809 is about 707.6785993656. The cubic root of 500809 is about 79.4128364470.

The spelling of 500809 in words is "five hundred thousand, eight hundred nine".