509191868 has 12 divisors (see below), whose sum is σ = 937985160. Its totient is φ = 241196112.

The previous prime is 509191799. The next prime is 509191877. The reversal of 509191868 is 868191905.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3349871 + ... + 3350022.

It is an arithmetic number, because the mean of its divisors is an integer number (78165430).

Almost surely, 2^509191868 is an apocalyptic number.

It is an amenable number.

509191868 is a deficient number, since it is larger than the sum of its proper divisors (428793292).

509191868 is a wasteful number, since it uses less digits than its factorization.

509191868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6699916 (or 6699914 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 47.

The square root of 509191868 is about 22565.2801445052. The cubic root of 509191868 is about 798.5347491885.

The spelling of 509191868 in words is "five hundred nine million, one hundred ninety-one thousand, eight hundred sixty-eight".