138538872 has 48 divisors (see below), whose sum is σ = 378944280. Its totient is φ = 45720000.

The previous prime is 138538853. The next prime is 138538879. The reversal of 138538872 is 278835831.

138538872 is a `hidden beast` number, since 1 + 38 + 538 + 87 + 2 = 666.

138538872 is digitally balanced in base 2, 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 (138538879) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2254 + ... + 16797.

Almost surely, 2^138538872 is an apocalyptic number.

138538872 is a gapful number since it is divisible by the number (12) 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 138538872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (189472140).

138538872 is an abundant number, since it is smaller than the sum of its proper divisors (240405408).

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

138538872 is a wasteful number, since it uses less digits than its factorization.

138538872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19164 (or 19157 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 138538872 is about 11770.2536931028. The cubic root of 138538872 is about 517.4366848254.

The spelling of 138538872 in words is "one hundred thirty-eight million, five hundred thirty-eight thousand, eight hundred seventy-two".