138293928 has 48 divisors (see below), whose sum is σ = 382524480. Its totient is φ = 45116064.

The previous prime is 138293899. The next prime is 138293971. The reversal of 138293928 is 829392831.

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

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17050 + ... + 23817.

It is an arithmetic number, because the mean of its divisors is an integer number (7969260).

Almost surely, 2^138293928 is an apocalyptic number.

138293928 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

138293928 is an abundant number, since it is smaller than the sum of its proper divisors (244230552).

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

138293928 is a wasteful number, since it uses less digits than its factorization.

138293928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40926 (or 40919 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 138293928 is about 11759.8438765147. The cubic root of 138293928 is about 517.1315531824.

The spelling of 138293928 in words is "one hundred thirty-eight million, two hundred ninety-three thousand, nine hundred twenty-eight".