66564868 has 6 divisors (see below), whose sum is σ = 116488526. Its totient is φ = 33282432.

The previous prime is 66564851. The next prime is 66564871. The reversal of 66564868 is 86846566.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 37920964 + 28643904 = 6158^2 + 5352^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8320605 + ... + 8320612.

Almost surely, 2^66564868 is an apocalyptic number.

It is an amenable number.

66564868 is a deficient number, since it is larger than the sum of its proper divisors (49923658).

66564868 is a wasteful number, since it uses less digits than its factorization.

66564868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16641221 (or 16641219 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 49.

The square root of 66564868 is about 8158.7295579643. The cubic root of 66564868 is about 405.2736412151.

The spelling of 66564868 in words is "sixty-six million, five hundred sixty-four thousand, eight hundred sixty-eight".