138732218 has 8 divisors (see below), whose sum is σ = 208928160. Its totient is φ = 69089500.

The previous prime is 138732211. The next prime is 138732227. The reversal of 138732218 is 812237831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×138732218² = 38493256622399048, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (138732211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137678 + ... + 138681.

It is an arithmetic number, because the mean of its divisors is an integer number (26116020).

Almost surely, 2^138732218 is an apocalyptic number.

138732218 is a deficient number, since it is larger than the sum of its proper divisors (70195942).

138732218 is a wasteful number, since it uses less digits than its factorization.

138732218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276612.

The product of its digits is 16128, while the sum is 35.

The square root of 138732218 is about 11778.4641613412. The cubic root of 138732218 is about 517.6772859096.

The spelling of 138732218 in words is "one hundred thirty-eight million, seven hundred thirty-two thousand, two hundred eighteen".