666438328 has 16 divisors (see below), whose sum is σ = 1292661000. Its totient is φ = 321728736.

The previous prime is 666438323. The next prime is 666438343. The reversal of 666438328 is 823834666.

666438328 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666438323) 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, 1436058 + ... + 1436521.

Almost surely, 2^666438328 is an apocalyptic number.

It is an amenable number.

666438328 is a deficient number, since it is larger than the sum of its proper divisors (626222672).

666438328 is a wasteful number, since it uses less digits than its factorization.

666438328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2872614 (or 2872610 counting only the distinct ones).

The product of its digits is 995328, while the sum is 46.

The square root of 666438328 is about 25815.4668367628. The cubic root of 666438328 is about 873.4807172481.

The spelling of 666438328 in words is "six hundred sixty-six million, four hundred thirty-eight thousand, three hundred twenty-eight".