138987888 has 120 divisors (see below), whose sum is σ = 408755088. Its totient is φ = 40449024.

The previous prime is 138987859. The next prime is 138987929. The reversal of 138987888 is 888789831.

138987888 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 224956 + ... + 225572.

Almost surely, 2^138987888 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 138987888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204377544).

138987888 is an abundant number, since it is smaller than the sum of its proper divisors (269767200).

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

138987888 is a wasteful number, since it uses less digits than its factorization.

138987888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679 (or 654 counting only the distinct ones).

The product of its digits is 6193152, while the sum is 60.

The square root of 138987888 is about 11789.3124481456. The cubic root of 138987888 is about 517.9951004044.

The spelling of 138987888 in words is "one hundred thirty-eight million, nine hundred eighty-seven thousand, eight hundred eighty-eight".