138338928 has 480 divisors, whose sum is σ = 545965056. Its totient is φ = 32845824.

The previous prime is 138338923. The next prime is 138338939. The reversal of 138338928 is 829833831.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138338923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6014725 + ... + 6014747.

Almost surely, 2^138338928 is an apocalyptic number.

138338928 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 138338928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (272982528).

138338928 is an abundant number, since it is smaller than the sum of its proper divisors (407626128).

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

138338928 is a wasteful number, since it uses less digits than its factorization.

138338928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 65 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 138338928 is about 11761.7570116033. The cubic root of 138338928 is about 517.1876375833.

The spelling of 138338928 in words is "one hundred thirty-eight million, three hundred thirty-eight thousand, nine hundred twenty-eight".