66510566165 has 8 divisors (see below), whose sum is σ = 84507543000. Its totient is φ = 50078543872.

The previous prime is 66510566149. The next prime is 66510566191. The reversal of 66510566165 is 56166501566.

It can be written as a sum of positive squares in 4 ways, for example, as 8413659076 + 58096907089 = 91726^2 + 241033^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 66510566165 - 2⁴ = 66510566149 is a prime.

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 7 ways as a sum of consecutive naturals, for example, 391238540 + ... + 391238709.

It is an arithmetic number, because the mean of its divisors is an integer number (10563442875).

Almost surely, 2^66510566165 is an apocalyptic number.

It is an amenable number.

66510566165 is a deficient number, since it is larger than the sum of its proper divisors (17996976835).

66510566165 is a wasteful number, since it uses less digits than its factorization.

66510566165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 782477271.

The product of its (nonzero) digits is 972000, while the sum is 47.

The spelling of 66510566165 in words is "sixty-six billion, five hundred ten million, five hundred sixty-six thousand, one hundred sixty-five".