666620432 has 20 divisors (see below), whose sum is σ = 1315948140. Its totient is φ = 327020928.

The previous prime is 666620401. The next prime is 666620489. The reversal of 666620432 is 234026666.

666620432 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 178917376 + 487703056 = 13376^2 + 22084^2 .

It is a junction number, because it is equal to n+sod(n) for n = 666620392 and 666620401.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 392207 + ... + 393902.

It is an arithmetic number, because the mean of its divisors is an integer number (65797407).

Almost surely, 2^666620432 is an apocalyptic number.

It is an amenable number.

666620432 is a deficient number, since it is larger than the sum of its proper divisors (649327708).

666620432 is a wasteful number, since it uses less digits than its factorization.

666620432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786170 (or 786164 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 35.

The square root of 666620432 is about 25818.9936287222. The cubic root of 666620432 is about 873.5602694186.

The spelling of 666620432 in words is "six hundred sixty-six million, six hundred twenty thousand, four hundred thirty-two".