66104523664 has 135 divisors (see below), whose sum is σ = 144317510577. Its totient is φ = 29322653184.

The previous prime is 66104523637. The next prime is 66104523677. The reversal of 66104523664 is 46632540166.

The square root of 66104523664 is 257108.

It is a perfect power (a square), and thus also a powerful number.

66104523664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 51465459600 + 14639064064 = 226860^2 + 120992^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66104523664.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 332183437 + ... + 332183635.

Almost surely, 2^66104523664 is an apocalyptic number.

66104523664 is the 257108-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66104523664

66104523664 is an abundant number, since it is smaller than the sum of its proper divisors (78212986913).

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

66104523664 is a wasteful number, since it uses less digits than its factorization.

66104523664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 43.

The spelling of 66104523664 in words is "sixty-six billion, one hundred four million, five hundred twenty-three thousand, six hundred sixty-four".