138778108 has 48 divisors (see below), whose sum is σ = 288630720. Its totient is φ = 57125376.

The previous prime is 138778093. The next prime is 138778177. The reversal of 138778108 is 801877831.

It is a happy number.

138778108 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×138778108³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 224616 + ... + 225232.

It is an arithmetic number, because the mean of its divisors is an integer number (6013140).

Almost surely, 2^138778108 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 138778108, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144315360).

138778108 is an abundant number, since it is smaller than the sum of its proper divisors (149852612).

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

138778108 is a wasteful number, since it uses less digits than its factorization.

138778108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934 (or 932 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 43.

The square root of 138778108 is about 11780.4120471230. The cubic root of 138778108 is about 517.7343589099.

The spelling of 138778108 in words is "one hundred thirty-eight million, seven hundred seventy-eight thousand, one hundred eight".