668517606 has 12 divisors (see below), whose sum is σ = 1448454852. Its totient is φ = 222839196.

The previous prime is 668517593. The next prime is 668517623. The reversal of 668517606 is 606715866.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18569916 + ... + 18569951.

It is an arithmetic number, because the mean of its divisors is an integer number (120704571).

Almost surely, 2^668517606 is an apocalyptic number.

668517606 is an abundant number, since it is smaller than the sum of its proper divisors (779937246).

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

668517606 is a wasteful number, since it uses less digits than its factorization.

668517606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37139875 (or 37139872 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 668517606 is about 25855.7074163520. The cubic root of 668517606 is about 874.3881898932.

The spelling of 668517606 in words is "six hundred sixty-eight million, five hundred seventeen thousand, six hundred six".