138664018 has 8 divisors (see below), whose sum is σ = 208077948. Its totient is φ = 69304704.

The previous prime is 138664013. The next prime is 138664027. The reversal of 138664018 is 810466831.

It can be written as a sum of positive squares in 2 ways, for example, as 137288089 + 1375929 = 11717^2 + 1173^2 .

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

It is not an unprimeable number, because it can be changed into a prime (138664013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6571 + ... + 17902.

Almost surely, 2^138664018 is an apocalyptic number.

138664018 is a deficient number, since it is larger than the sum of its proper divisors (69413930).

138664018 is a wasteful number, since it uses less digits than its factorization.

138664018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27308.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 138664018 is about 11775.5686911503. The cubic root of 138664018 is about 517.5924428973.

The spelling of 138664018 in words is "one hundred thirty-eight million, six hundred sixty-four thousand, eighteen".