18989808 has 20 divisors (see below), whose sum is σ = 49057128. Its totient is φ = 6329920.

The previous prime is 18989807. The next prime is 18989821. The reversal of 18989808 is 80898981.

It is a super-2 number, since 2×18989808² = 721225615753728, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18989807) 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, 197763 + ... + 197858.

Almost surely, 2^18989808 is an apocalyptic number.

It is an amenable number.

18989808 is an abundant number, since it is smaller than the sum of its proper divisors (30067320).

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

18989808 is a wasteful number, since it uses less digits than its factorization.

18989808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395632 (or 395626 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 51.

The square root of 18989808 is about 4357.7296841360. The cubic root of 18989808 is about 266.7924434442.

The spelling of 18989808 in words is "eighteen million, nine hundred eighty-nine thousand, eight hundred eight".