198987128 has 16 divisors (see below), whose sum is σ = 374091000. Its totient is φ = 99229536.

The previous prime is 198987127. The next prime is 198987161. The reversal of 198987128 is 821789891.

It is a happy number.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 198987128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198987121) 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, 29783 + ... + 35846.

Almost surely, 2^198987128 is an apocalyptic number.

It is an amenable number.

198987128 is a deficient number, since it is larger than the sum of its proper divisors (175103872).

198987128 is a wasteful number, since it uses less digits than its factorization.

198987128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66014 (or 66010 counting only the distinct ones).

The product of its digits is 580608, while the sum is 53.

The square root of 198987128 is about 14106.2797363444. The cubic root of 198987128 is about 583.8146578296.

The spelling of 198987128 in words is "one hundred ninety-eight million, nine hundred eighty-seven thousand, one hundred twenty-eight".