668505717975 has 24 divisors (see below), whose sum is σ = 1120403382352. Its totient is φ = 351652320000.

The previous prime is 668505717953. The next prime is 668505718061. The reversal of 668505717975 is 579717505866.

It is a happy number.

It is not a de Polignac number, because 668505717975 - 2⁹ = 668505717463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61045276 + ... + 61056225.

Almost surely, 2^668505717975 is an apocalyptic number.

668505717975 is a deficient number, since it is larger than the sum of its proper divisors (451897664377).

668505717975 is a wasteful number, since it uses less digits than its factorization.

668505717975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122101587 (or 122101582 counting only the distinct ones).

The product of its (nonzero) digits is 111132000, while the sum is 66.

The spelling of 668505717975 in words is "six hundred sixty-eight billion, five hundred five million, seven hundred seventeen thousand, nine hundred seventy-five".