2165181 has 8 divisors (see below), whose sum is σ = 2898720. Its totient is φ = 1437552.

The previous prime is 2165159. The next prime is 2165201. The reversal of 2165181 is 1815612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2165181 - 2⁶ = 2165117 is a prime.

It is a super-2 number, since 2×2165181² = 9376017525522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2165131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 535 + ... + 2148.

It is an arithmetic number, because the mean of its divisors is an integer number (362340).

2^2165181 is an apocalyptic number.

It is an amenable number.

2165181 is a deficient number, since it is larger than the sum of its proper divisors (733539).

2165181 is a wasteful number, since it uses less digits than its factorization.

2165181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2955.

The product of its digits is 480, while the sum is 24.

The square root of 2165181 is about 1471.4554019745. The cubic root of 2165181 is about 129.3693518970.

It can be divided in two parts, 2165 and 181, that added together give a triangular number (2346 = T₆₈).

The spelling of 2165181 in words is "two million, one hundred sixty-five thousand, one hundred eighty-one".