18557808 has 20 divisors (see below), whose sum is σ = 47941128. Its totient is φ = 6185920.

The previous prime is 18557807. The next prime is 18557821. The reversal of 18557808 is 80875581.

It is a self number, because there is not a number n which added to its sum of digits gives 18557808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18557807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193263 + ... + 193358.

Almost surely, 2^18557808 is an apocalyptic number.

It is an amenable number.

18557808 is an abundant number, since it is smaller than the sum of its proper divisors (29383320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18557808 is a wasteful number, since it uses less digits than its factorization.

18557808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386632 (or 386626 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 42.

The square root of 18557808 is about 4307.8774355824. The cubic root of 18557808 is about 264.7538143209.

The spelling of 18557808 in words is "eighteen million, five hundred fifty-seven thousand, eight hundred eight".