2165188131 has 8 divisors (see below), whose sum is σ = 3207686160. Its totient is φ = 1443458736.

The previous prime is 2165188093. The next prime is 2165188189. The reversal of 2165188131 is 1318815612.

2165188131 is a `hidden beast` number, since 2 + 1 + 6 + 518 + 8 + 131 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-2165188131 is a prime.

It is a super-2 number, since 2×2165188131² = 9376079285246546322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2165188031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40096050 + ... + 40096103.

It is an arithmetic number, because the mean of its divisors is an integer number (400960770).

Almost surely, 2^2165188131 is an apocalyptic number.

2165188131 is a deficient number, since it is larger than the sum of its proper divisors (1042498029).

2165188131 is an equidigital number, since it uses as much as digits as its factorization.

2165188131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80192162 (or 80192156 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 2165188131 is about 46531.5820814208. The cubic root of 2165188131 is about 1293.6949392236.

The spelling of 2165188131 in words is "two billion, one hundred sixty-five million, one hundred eighty-eight thousand, one hundred thirty-one".