66605165 has 16 divisors (see below), whose sum is σ = 91782720. Its totient is φ = 45889920.

The previous prime is 66605117. The next prime is 66605179. The reversal of 66605165 is 56150666.

It is not a de Polignac number, because 66605165 - 2²⁴ = 49827949 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 15 ways as a sum of consecutive naturals, for example, 30824 + ... + 32913.

It is an arithmetic number, because the mean of its divisors is an integer number (5736420).

Almost surely, 2^66605165 is an apocalyptic number.

It is an amenable number.

66605165 is a deficient number, since it is larger than the sum of its proper divisors (25177555).

66605165 is a wasteful number, since it uses less digits than its factorization.

66605165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63772.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 66605165 is about 8161.1987477331. The cubic root of 66605165 is about 405.3554061559.

The spelling of 66605165 in words is "sixty-six million, six hundred five thousand, one hundred sixty-five".