138673920 has 432 divisors, whose sum is σ = 570423168. Its totient is φ = 28385280.

The previous prime is 138673903. The next prime is 138673921. The reversal of 138673920 is 29376831.

138673920 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 not an unprimeable number, because it can be changed into a prime (138673921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2069727 + ... + 2069793.

It is an arithmetic number, because the mean of its divisors is an integer number (1320424).

Almost surely, 2^138673920 is an apocalyptic number.

138673920 is a gapful number since it is divisible by the number (10) 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 138673920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285211584).

138673920 is an abundant number, since it is smaller than the sum of its proper divisors (431749248).

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

138673920 is a wasteful number, since it uses less digits than its factorization.

138673920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 39.

The square root of 138673920 is about 11775.9891304298. The cubic root of 138673920 is about 517.6047630326.

The spelling of 138673920 in words is "one hundred thirty-eight million, six hundred seventy-three thousand, nine hundred twenty".