664646272 has 64 divisors (see below), whose sum is σ = 1387575360. Its totient is φ = 316518400.

The previous prime is 664646267. The next prime is 664646287. The reversal of 664646272 is 272646466.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1180263 + ... + 1180825.

It is an arithmetic number, because the mean of its divisors is an integer number (21680865).

Almost surely, 2^664646272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664646272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (693787680).

664646272 is an abundant number, since it is smaller than the sum of its proper divisors (722929088).

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

664646272 is a wasteful number, since it uses less digits than its factorization.

664646272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1001 (or 989 counting only the distinct ones).

The product of its digits is 580608, while the sum is 43.

The square root of 664646272 is about 25780.7345124223. The cubic root of 664646272 is about 872.6970830887.

The spelling of 664646272 in words is "six hundred sixty-four million, six hundred forty-six thousand, two hundred seventy-two".