66721216626175 has 24 divisors (see below), whose sum is σ = 87216255480960. Its totient is φ = 50493621103200.

The previous prime is 66721216626173. The next prime is 66721216626223. The reversal of 66721216626175 is 57162661212766.

It is not a de Polignac number, because 66721216626175 - 2¹ = 66721216626173 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66721216626173) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 102505531 + ... + 103154380.

It is an arithmetic number, because the mean of its divisors is an integer number (3634010645040).

Almost surely, 2^{66721216626175} is an apocalyptic number.

66721216626175 is a deficient number, since it is larger than the sum of its proper divisors (20495038854785).

66721216626175 is a wasteful number, since it uses less digits than its factorization.

66721216626175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205660623 (or 205660618 counting only the distinct ones).

The product of its digits is 15240960, while the sum is 58.

The spelling of 66721216626175 in words is "sixty-six trillion, seven hundred twenty-one billion, two hundred sixteen million, six hundred twenty-six thousand, one hundred seventy-five".