2165564304123 has 16 divisors (see below), whose sum is σ = 3223165478016. Its totient is φ = 1281940813440.

The previous prime is 2165564304119. The next prime is 2165564304161. The reversal of 2165564304123 is 3214034655612.

It is not a de Polignac number, because 2165564304123 - 2² = 2165564304119 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2165564306123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 763058590 + ... + 763061427.

It is an arithmetic number, because the mean of its divisors is an integer number (201447842376).

Almost surely, 2^{2165564304123} is an apocalyptic number.

2165564304123 is a deficient number, since it is larger than the sum of its proper divisors (1057601173893).

2165564304123 is a wasteful number, since it uses less digits than its factorization.

2165564304123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1526120074.

The product of its (nonzero) digits is 518400, while the sum is 42.

Adding to 2165564304123 its reverse (3214034655612), we get a palindrome (5379598959735).

The spelling of 2165564304123 in words is "two trillion, one hundred sixty-five billion, five hundred sixty-four million, three hundred four thousand, one hundred twenty-three".