664523872 has 24 divisors (see below), whose sum is σ = 1313388216. Its totient is φ = 330964992.

The previous prime is 664523869. The next prime is 664523921. The reversal of 664523872 is 278325466.

664523872 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 (43) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32178 + ... + 48625.

It is an arithmetic number, because the mean of its divisors is an integer number (54724509).

Almost surely, 2^664523872 is an apocalyptic number.

It is an amenable number.

664523872 is a deficient number, since it is larger than the sum of its proper divisors (648864344).

664523872 is a wasteful number, since it uses less digits than its factorization.

664523872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81070 (or 81062 counting only the distinct ones).

The product of its digits is 483840, while the sum is 43.

The square root of 664523872 is about 25778.3605374741. The cubic root of 664523872 is about 872.6435083852.

The spelling of 664523872 in words is "six hundred sixty-four million, five hundred twenty-three thousand, eight hundred seventy-two".