668945392128 has 480 divisors, whose sum is σ = 2188671541056. Its totient is φ = 202724425728.

The previous prime is 668945392117. The next prime is 668945392147. The reversal of 668945392128 is 821293549866.

668945392128 is a `hidden beast` number, since 6 + 6 + 8 + 94 + 539 + 2 + 1 + 2 + 8 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 108363250 + ... + 108369422.

Almost surely, 2^668945392128 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 668945392128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1094335770528).

668945392128 is an abundant number, since it is smaller than the sum of its proper divisors (1519726148928).

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

668945392128 is an equidigital number, since it uses as much as digits as its factorization.

668945392128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6286 (or 6258 counting only the distinct ones).

The product of its digits is 44789760, while the sum is 63.

The spelling of 668945392128 in words is "six hundred sixty-eight billion, nine hundred forty-five million, three hundred ninety-two thousand, one hundred twenty-eight".