664945813500696 has 2048 divisors, whose sum is σ = 2601123840000000. Its totient is φ = 155418872684544.

The previous prime is 664945813500643. The next prime is 664945813500737. The reversal of 664945813500696 is 696005318549466.

664945813500696 is a `hidden beast` number, since 6 + 6 + 4 + 9 + 4 + 58 + 1 + 3 + 500 + 69 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 51952944105 + ... + 51952956903.

It is an arithmetic number, because the mean of its divisors is an integer number (1270080000000).

Almost surely, 2^{664945813500696} 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 664945813500696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1300561920000000).

664945813500696 is an abundant number, since it is smaller than the sum of its proper divisors (1936178026499304).

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

664945813500696 is a wasteful number, since it uses less digits than its factorization.

664945813500696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13051 (or 13027 counting only the distinct ones).

The product of its (nonzero) digits is 1007769600, while the sum is 72.

The spelling of 664945813500696 in words is "six hundred sixty-four trillion, nine hundred forty-five billion, eight hundred thirteen million, five hundred thousand, six hundred ninety-six".