668693515776 has 320 divisors, whose sum is σ = 2106321186816. Its totient is φ = 185846169600.

The previous prime is 668693515753. The next prime is 668693515801. The reversal of 668693515776 is 677515396866.

It is a self number, because there is not a number n which added to its sum of digits gives 668693515776.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34475041 + ... + 34494431.

Almost surely, 2^668693515776 is an apocalyptic number.

668693515776 is a gapful number since it is divisible by the number (66) 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 668693515776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1053160593408).

668693515776 is an abundant number, since it is smaller than the sum of its proper divisors (1437627671040).

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

668693515776 is a wasteful number, since it uses less digits than its factorization.

668693515776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19593 (or 19577 counting only the distinct ones).

The product of its digits is 342921600, while the sum is 69.

The spelling of 668693515776 in words is "six hundred sixty-eight billion, six hundred ninety-three million, five hundred fifteen thousand, seven hundred seventy-six".