138538578 has 16 divisors (see below), whose sum is σ = 277285536. Its totient is φ = 46144800.

The previous prime is 138538577. The next prime is 138538583. The reversal of 138538578 is 875835831.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (138538577) 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, 750 + ... + 16662.

It is an arithmetic number, because the mean of its divisors is an integer number (17330346).

Almost surely, 2^138538578 is an apocalyptic number.

138538578 is an abundant number, since it is smaller than the sum of its proper divisors (138746958).

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

138538578 is a wasteful number, since it uses less digits than its factorization.

138538578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17369.

The product of its digits is 806400, while the sum is 48.

The square root of 138538578 is about 11770.2412039856. The cubic root of 138538578 is about 517.4363187994.

The spelling of 138538578 in words is "one hundred thirty-eight million, five hundred thirty-eight thousand, five hundred seventy-eight".