19998188 has 24 divisors (see below), whose sum is σ = 42350112. Its totient is φ = 8066304.

The previous prime is 19998169. The next prime is 19998217. The reversal of 19998188 is 88189991.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20531 + ... + 21482.

It is an arithmetic number, because the mean of its divisors is an integer number (1764588).

Almost surely, 2^19998188 is an apocalyptic number.

It is an amenable number.

19998188 is an abundant number, since it is smaller than the sum of its proper divisors (22351924).

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

19998188 is a wasteful number, since it uses less digits than its factorization.

19998188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42041 (or 42039 counting only the distinct ones).

The product of its digits is 373248, while the sum is 53.

The square root of 19998188 is about 4471.9333626520. The cubic root of 19998188 is about 271.4335638707.

The spelling of 19998188 in words is "nineteen million, nine hundred ninety-eight thousand, one hundred eighty-eight".