18189808 has 90 divisors (see below), whose sum is σ = 45066312. Its totient is φ = 6963840.

The previous prime is 18189793. The next prime is 18189823. The reversal of 18189808 is 80898181.

It is an interprime number because it is at equal distance from previous prime (18189793) and next prime (18189823).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 586753 + ... + 586783.

Almost surely, 2^18189808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18189808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22533156).

18189808 is an abundant number, since it is smaller than the sum of its proper divisors (26876504).

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

18189808 is a wasteful number, since it uses less digits than its factorization.

18189808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 43.

The square root of 18189808 is about 4264.9511134361. The cubic root of 18189808 is about 262.9921012341.

The spelling of 18189808 in words is "eighteen million, one hundred eighty-nine thousand, eight hundred eight".