668071812 has 12 divisors (see below), whose sum is σ = 1558834256. Its totient is φ = 222690600.

The previous prime is 668071801. The next prime is 668071843. The reversal of 668071812 is 218170866.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27836314 + ... + 27836337.

Almost surely, 2^668071812 is an apocalyptic number.

It is an amenable number.

668071812 is an abundant number, since it is smaller than the sum of its proper divisors (890762444).

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

668071812 is a wasteful number, since it uses less digits than its factorization.

668071812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55672658 (or 55672656 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 39.

The square root of 668071812 is about 25847.0851741546. The cubic root of 668071812 is about 874.1937877906.

The spelling of 668071812 in words is "six hundred sixty-eight million, seventy-one thousand, eight hundred twelve".