2165866365 has 16 divisors (see below), whose sum is σ = 3731954688. Its totient is φ = 1066272576.

The previous prime is 2165866349. The next prime is 2165866379. The reversal of 2165866365 is 5636685612.

It is not a de Polignac number, because 2165866365 - 2⁴ = 2165866349 is a prime.

It is a super-2 number, since 2×2165866365² = 9381954222076626450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5553309 + ... + 5553698.

It is an arithmetic number, because the mean of its divisors is an integer number (233247168).

Almost surely, 2^2165866365 is an apocalyptic number.

It is an amenable number.

2165866365 is a deficient number, since it is larger than the sum of its proper divisors (1566088323).

2165866365 is a wasteful number, since it uses less digits than its factorization.

2165866365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11107028.

The product of its digits is 1555200, while the sum is 48.

The square root of 2165866365 is about 46538.8693996749. The cubic root of 2165866365 is about 1293.8300062077.

The spelling of 2165866365 in words is "two billion, one hundred sixty-five million, eight hundred sixty-six thousand, three hundred sixty-five".