66605665604 has 24 divisors (see below), whose sum is σ = 118410788160. Its totient is φ = 32774946336.

The previous prime is 66605665601. The next prime is 66605665619. The reversal of 66605665604 is 40656650666.

It is not an unprimeable number, because it can be changed into a prime (66605665601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170249 + ... + 402735.

It is an arithmetic number, because the mean of its divisors is an integer number (4933782840).

Almost surely, 2^66605665604 is an apocalyptic number.

It is an amenable number.

66605665604 is a deficient number, since it is larger than the sum of its proper divisors (51805122556).

66605665604 is a wasteful number, since it uses less digits than its factorization.

66605665604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233627 (or 233625 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 50.

The spelling of 66605665604 in words is "sixty-six billion, six hundred five million, six hundred sixty-five thousand, six hundred four".