664648064 has 64 divisors (see below), whose sum is σ = 1359998640. Its totient is φ = 323444736.

The previous prime is 664648021. The next prime is 664648067. The reversal of 664648064 is 460846466.

664648064 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664648067) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 775124 + ... + 775980.

Almost surely, 2^664648064 is an apocalyptic number.

664648064 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664648064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (679999320).

664648064 is an abundant number, since it is smaller than the sum of its proper divisors (695350576).

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

664648064 is an equidigital number, since it uses as much as digits as its factorization.

664648064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1027 (or 1015 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 44.

The square root of 664648064 is about 25780.7692670331. The cubic root of 664648064 is about 872.6978674015.

The spelling of 664648064 in words is "six hundred sixty-four million, six hundred forty-eight thousand, sixty-four".