138538944 has 56 divisors (see below), whose sum is σ = 407283920. Its totient is φ = 46179072.

The previous prime is 138538943. The next prime is 138538951. The reversal of 138538944 is 449835831.

It is a self number, because there is not a number n which added to its sum of digits gives 138538944.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138538943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38359 + ... + 41814.

Almost surely, 2^138538944 is an apocalyptic number.

It is an amenable number.

138538944 is an abundant number, since it is smaller than the sum of its proper divisors (268744976).

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

138538944 is an equidigital number, since it uses as much as digits as its factorization.

138538944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80194 (or 80178 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 138538944 is about 11770.2567516601. The cubic root of 138538944 is about 517.4367744644.

The spelling of 138538944 in words is "one hundred thirty-eight million, five hundred thirty-eight thousand, nine hundred forty-four".