138736218 has 16 divisors (see below), whose sum is σ = 293794560. Its totient is φ = 43525056.

The previous prime is 138736217. The next prime is 138736237. The reversal of 138736218 is 812637831.

It is not an unprimeable number, because it can be changed into a prime (138736211) 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, 679978 + ... + 680181.

It is an arithmetic number, because the mean of its divisors is an integer number (18362160).

Almost surely, 2^138736218 is an apocalyptic number.

138736218 is an abundant number, since it is smaller than the sum of its proper divisors (155058342).

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

138736218 is a wasteful number, since it uses less digits than its factorization.

138736218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360181.

The product of its digits is 48384, while the sum is 39.

The square root of 138736218 is about 11778.6339615424. The cubic root of 138736218 is about 517.6822611761.

The spelling of 138736218 in words is "one hundred thirty-eight million, seven hundred thirty-six thousand, two hundred eighteen".