66704661584 has 20 divisors (see below), whose sum is σ = 140989398720. Its totient is φ = 30320300640.

The previous prime is 66704661581. The next prime is 66704661599. The reversal of 66704661584 is 48516640766.

66704661584 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66704661581) 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, 189501704 + ... + 189502055.

It is an arithmetic number, because the mean of its divisors is an integer number (7049469936).

Almost surely, 2^66704661584 is an apocalyptic number.

It is an amenable number.

66704661584 is an abundant number, since it is smaller than the sum of its proper divisors (74284737136).

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

66704661584 is a wasteful number, since it uses less digits than its factorization.

66704661584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379003778 (or 379003772 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 53.

The spelling of 66704661584 in words is "sixty-six billion, seven hundred four million, six hundred sixty-one thousand, five hundred eighty-four".