668932719840 has 2880 divisors, whose sum is σ = 3270637294848. Its totient is φ = 126804787200.

The previous prime is 668932719787. The next prime is 668932719881. The reversal of 668932719840 is 48917239866.

668932719840 is a `hidden beast` number, since 6 + 6 + 89 + 327 + 198 + 40 = 666.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 5106356575 + ... + 5106356705.

Almost surely, 2^668932719840 is an apocalyptic number.

668932719840 is a gapful number since it is divisible by the number (60) 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 668932719840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1635318647424).

668932719840 is an abundant number, since it is smaller than the sum of its proper divisors (2601704575008).

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

668932719840 is a wasteful number, since it uses less digits than its factorization.

668932719840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243 (or 219 counting only the distinct ones).

The product of its (nonzero) digits is 31352832, while the sum is 63.

The spelling of 668932719840 in words is "six hundred sixty-eight billion, nine hundred thirty-two million, seven hundred nineteen thousand, eight hundred forty".