66688568 has 8 divisors (see below), whose sum is σ = 125041080. Its totient is φ = 33344280.

The previous prime is 66688549. The next prime is 66688577. The reversal of 66688568 is 86588666.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4168028 + ... + 4168043.

It is an arithmetic number, because the mean of its divisors is an integer number (15630135).

Almost surely, 2^66688568 is an apocalyptic number.

It is an amenable number.

66688568 is a deficient number, since it is larger than the sum of its proper divisors (58352512).

66688568 is a wasteful number, since it uses less digits than its factorization.

66688568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8336077 (or 8336073 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 53.

The square root of 66688568 is about 8166.3068764283. The cubic root of 66688568 is about 405.5245309545.

The spelling of 66688568 in words is "sixty-six million, six hundred eighty-eight thousand, five hundred sixty-eight".