388128138 has 32 divisors (see below), whose sum is σ = 782960256. Its totient is φ = 128264448.

The previous prime is 388128133. The next prime is 388128157. The reversal of 388128138 is 831821883.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 388128138.

It is not an unprimeable number, because it can be changed into a prime (388128131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 437131 + ... + 438017.

It is an arithmetic number, because the mean of its divisors is an integer number (24467508).

Almost surely, 2^388128138 is an apocalyptic number.

388128138 is an abundant number, since it is smaller than the sum of its proper divisors (394832118).

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

388128138 is a wasteful number, since it uses less digits than its factorization.

388128138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1438.

The product of its digits is 73728, while the sum is 42.

The square root of 388128138 is about 19700.9679457635. The cubic root of 388128138 is about 729.4435855099.

The spelling of 388128138 in words is "three hundred eighty-eight million, one hundred twenty-eight thousand, one hundred thirty-eight".