138359988 has 120 divisors (see below), whose sum is σ = 394444512. Its totient is φ = 42037056.

The previous prime is 138359959. The next prime is 138359993. The reversal of 138359988 is 889953831.

138359988 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

Its product of digits (1866240) is a multiple of the sum of its prime divisors (432).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 450531 + ... + 450837.

Almost surely, 2^138359988 is an apocalyptic number.

138359988 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138359988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197222256).

138359988 is an abundant number, since it is smaller than the sum of its proper divisors (256084524).

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

138359988 is a wasteful number, since it uses less digits than its factorization.

138359988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443 (or 432 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 54.

The square root of 138359988 is about 11762.6522519371. The cubic root of 138359988 is about 517.2138809050.

The spelling of 138359988 in words is "one hundred thirty-eight million, three hundred fifty-nine thousand, nine hundred eighty-eight".