138039808 has 40 divisors (see below), whose sum is σ = 276946560. Its totient is φ = 68736000.

The previous prime is 138039793. The next prime is 138039817. The reversal of 138039808 is 808930831.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183433 + ... + 184183.

It is an arithmetic number, because the mean of its divisors is an integer number (6923664).

Almost surely, 2^138039808 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 138039808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138473280).

138039808 is an abundant number, since it is smaller than the sum of its proper divisors (138906752).

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

138039808 is an frugal number, since it uses more digits than its factorization.

138039808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1128 (or 1112 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 138039808 is about 11749.0343432982. The cubic root of 138039808 is about 516.8146097785.

The spelling of 138039808 in words is "one hundred thirty-eight million, thirty-nine thousand, eight hundred eight".