668690476608 has 448 divisors, whose sum is σ = 2282218334208. Its totient is φ = 167739310080.

The previous prime is 668690476583. The next prime is 668690476637. The reversal of 668690476608 is 806674096866.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (66).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 74935635 + ... + 74944557.

Almost surely, 2^668690476608 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 668690476608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1141109167104).

668690476608 is an abundant number, since it is smaller than the sum of its proper divisors (1613527857600).

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

668690476608 is a wasteful number, since it uses less digits than its factorization.

668690476608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9130 (or 9120 counting only the distinct ones).

The product of its (nonzero) digits is 125411328, while the sum is 66.

The spelling of 668690476608 in words is "six hundred sixty-eight billion, six hundred ninety million, four hundred seventy-six thousand, six hundred eight".