66604128 has 24 divisors (see below), whose sum is σ = 174836088. Its totient is φ = 22201344.

The previous prime is 66604127. The next prime is 66604163. The reversal of 66604128 is 82140666.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×66604128² = 8872219733280768, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66604127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 346801 + ... + 346992.

It is an arithmetic number, because the mean of its divisors is an integer number (7284837).

Almost surely, 2^66604128 is an apocalyptic number.

It is an amenable number.

66604128 is an abundant number, since it is smaller than the sum of its proper divisors (108231960).

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

66604128 is a wasteful number, since it uses less digits than its factorization.

66604128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693806 (or 693798 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 66604128 is about 8161.1352151524. The cubic root of 66604128 is about 405.3533024365.

The spelling of 66604128 in words is "sixty-six million, six hundred four thousand, one hundred twenty-eight".