138135678 has 16 divisors (see below), whose sum is σ = 276965136. Its totient is φ = 45929600.

The previous prime is 138135667. The next prime is 138135691. The reversal of 138135678 is 876531831.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26301 + ... + 31112.

It is an arithmetic number, because the mean of its divisors is an integer number (17310321).

Almost surely, 2^138135678 is an apocalyptic number.

138135678 is an abundant number, since it is smaller than the sum of its proper divisors (138829458).

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

138135678 is a wasteful number, since it uses less digits than its factorization.

138135678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57819.

The product of its digits is 120960, while the sum is 42.

The square root of 138135678 is about 11753.1135449293. The cubic root of 138135678 is about 516.9342263622.

It can be divided in two parts, 13813 and 5678, that added together give a palindrome (19491).

The spelling of 138135678 in words is "one hundred thirty-eight million, one hundred thirty-five thousand, six hundred seventy-eight".