2165903931185 has 4 divisors (see below), whose sum is σ = 2599084717428. Its totient is φ = 1732723144944.

The previous prime is 2165903931097. The next prime is 2165903931227. The reversal of 2165903931185 is 5811393095612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 949050052864 + 1216853878321 = 974192^2 + 1103111^2 .

It is a cyclic number.

It is not a de Polignac number, because 2165903931185 - 2¹⁰ = 2165903930161 is a prime.

It is a super-2 number, since 2×2165903931185² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 216590393114 + ... + 216590393123.

It is an arithmetic number, because the mean of its divisors is an integer number (649771179357).

Almost surely, 2^{2165903931185} is an apocalyptic number.

It is an amenable number.

2165903931185 is a deficient number, since it is larger than the sum of its proper divisors (433180786243).

2165903931185 is an equidigital number, since it uses as much as digits as its factorization.

2165903931185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433180786242.

The product of its (nonzero) digits is 1749600, while the sum is 53.

The spelling of 2165903931185 in words is "two trillion, one hundred sixty-five billion, nine hundred three million, nine hundred thirty-one thousand, one hundred eighty-five".