668468578272768 has 2560 divisors, whose sum is σ = 2570730822696960. Its totient is φ = 166797066240000.

The previous prime is 668468578272611. The next prime is 668468578272793. The reversal of 668468578272768 is 867272875864866.

668468578272768 is a `hidden beast` number, since 6 + 6 + 8 + 4 + 6 + 8 + 578 + 2 + 7 + 27 + 6 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 351640492618 + ... + 351640494518.

It is an arithmetic number, because the mean of its divisors is an integer number (1004191727616).

Almost surely, 2^{668468578272768} 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 668468578272768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1285365411348480).

668468578272768 is an abundant number, since it is smaller than the sum of its proper divisors (1902262244424192).

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

668468578272768 is a wasteful number, since it uses less digits than its factorization.

668468578272768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2177 (or 2155 counting only the distinct ones).

The product of its digits is 145662935040, while the sum is 90.

The spelling of 668468578272768 in words is "six hundred sixty-eight trillion, four hundred sixty-eight billion, five hundred seventy-eight million, two hundred seventy-two thousand, seven hundred sixty-eight".