188638641 has 6 divisors (see below), whose sum is σ = 272478050. Its totient is φ = 125759088.

The previous prime is 188638601. The next prime is 188638717. The reversal of 188638641 is 146836881.

It is a happy number.

188638641 is a `hidden beast` number, since 1 + 8 + 8 + 638 + 6 + 4 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 186896241 + 1742400 = 13671^2 + 1320^2 .

It is not a de Polignac number, because 188638641 - 2⁹ = 188638129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (188638601) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10479916 + ... + 10479933.

Almost surely, 2^188638641 is an apocalyptic number.

It is an amenable number.

188638641 is a deficient number, since it is larger than the sum of its proper divisors (83839409).

188638641 is a wasteful number, since it uses less digits than its factorization.

188638641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20959855 (or 20959852 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 188638641 is about 13734.5782971302. The cubic root of 188638641 is about 573.5133781562.

The spelling of 188638641 in words is "one hundred eighty-eight million, six hundred thirty-eight thousand, six hundred forty-one".