666721307118 has 8 divisors (see below), whose sum is σ = 1333442614248. Its totient is φ = 222240435704.

The previous prime is 666721307107. The next prime is 666721307141. The reversal of 666721307118 is 811703127666.

It is a sphenic number, since it is the product of 3 distinct primes.

666721307118 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55560108921 + ... + 55560108932.

It is an arithmetic number, because the mean of its divisors is an integer number (166680326781).

Almost surely, 2^666721307118 is an apocalyptic number.

666721307118 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

666721307118 is a wasteful number, since it uses less digits than its factorization.

666721307118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111120217858.

The product of its (nonzero) digits is 508032, while the sum is 48.

The spelling of 666721307118 in words is "six hundred sixty-six billion, seven hundred twenty-one million, three hundred seven thousand, one hundred eighteen".