138533878 has 24 divisors (see below), whose sum is σ = 242804952. Its totient is φ = 59107104.

The previous prime is 138533869. The next prime is 138533881. The reversal of 138533878 is 878335831.

It is a congruent number.

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, 19801 + ... + 25867.

It is an arithmetic number, because the mean of its divisors is an integer number (10116873).

Almost surely, 2^138533878 is an apocalyptic number.

138533878 is a deficient number, since it is larger than the sum of its proper divisors (104271074).

138533878 is a wasteful number, since it uses less digits than its factorization.

138533878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6316 (or 6309 counting only the distinct ones).

The product of its digits is 483840, while the sum is 46.

The square root of 138533878 is about 11770.0415462308. The cubic root of 138533878 is about 517.4304672928.

The spelling of 138533878 in words is "one hundred thirty-eight million, five hundred thirty-three thousand, eight hundred seventy-eight".