664688512512 has 640 divisors, whose sum is σ = 2137933163520. Its totient is φ = 203352145920.

The previous prime is 664688512507. The next prime is 664688512513. The reversal of 664688512512 is 215215886466.

664688512512 is a `hidden beast` number, since 6 + 6 + 46 + 8 + 85 + 1 + 2 + 512 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664688512513) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 833987698 + ... + 833988494.

It is an arithmetic number, because the mean of its divisors is an integer number (3340520568).

Almost surely, 2^664688512512 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 664688512512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1068966581760).

664688512512 is an abundant number, since it is smaller than the sum of its proper divisors (1473244651008).

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

664688512512 is a wasteful number, since it uses less digits than its factorization.

664688512512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 951 (or 929 counting only the distinct ones).

The product of its digits is 5529600, while the sum is 54.

The spelling of 664688512512 in words is "six hundred sixty-four billion, six hundred eighty-eight million, five hundred twelve thousand, five hundred twelve".