66645604 has 6 divisors (see below), whose sum is σ = 116629814. Its totient is φ = 33322800.

The previous prime is 66645599. The next prime is 66645619. The reversal of 66645604 is 40654666.

It can be written as a sum of positive squares in only one way, i.e., 42928704 + 23716900 = 6552^2 + 4870^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8330697 + ... + 8330704.

Almost surely, 2^66645604 is an apocalyptic number.

It is an amenable number.

66645604 is a deficient number, since it is larger than the sum of its proper divisors (49984210).

66645604 is a wasteful number, since it uses less digits than its factorization.

66645604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16661405 (or 16661403 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 37.

The square root of 66645604 is about 8163.6758877359. The cubic root of 66645604 is about 405.4374260759.

The spelling of 66645604 in words is "sixty-six million, six hundred forty-five thousand, six hundred four".