666425321604 has 36 divisors (see below), whose sum is σ = 1925228707584. Its totient is φ = 190407234672.

The previous prime is 666425321593. The next prime is 666425321633. The reversal of 666425321604 is 406123524666.

It is a happy number.

666425321604 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 666425321604.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1322272212 + ... + 1322272715.

Almost surely, 2^666425321604 is an apocalyptic number.

It is an amenable number.

666425321604 is an abundant number, since it is smaller than the sum of its proper divisors (1258803385980).

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

666425321604 is a wasteful number, since it uses less digits than its factorization.

666425321604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2644544944 (or 2644544939 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 45.

The spelling of 666425321604 in words is "six hundred sixty-six billion, four hundred twenty-five million, three hundred twenty-one thousand, six hundred four".