66511561165 has 32 divisors (see below), whose sum is σ = 92160737280. Its totient is φ = 45137736000.

The previous prime is 66511561133. The next prime is 66511561183. The reversal of 66511561165 is 56116511566.

It is not a de Polignac number, because 66511561165 - 2⁵ = 66511561133 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1409016 + ... + 1455454.

It is an arithmetic number, because the mean of its divisors is an integer number (2880023040).

Almost surely, 2^66511561165 is an apocalyptic number.

It is an amenable number.

66511561165 is a deficient number, since it is larger than the sum of its proper divisors (25649176115).

66511561165 is a wasteful number, since it uses less digits than its factorization.

66511561165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46873.

The product of its digits is 162000, while the sum is 43.

The spelling of 66511561165 in words is "sixty-six billion, five hundred eleven million, five hundred sixty-one thousand, one hundred sixty-five".