2161166109 has 4 divisors (see below), whose sum is σ = 2881554816. Its totient is φ = 1440777404.

The previous prime is 2161166093. The next prime is 2161166131. The reversal of 2161166109 is 9016611612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2161166109 - 2⁴ = 2161166093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2161166109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161166309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360194349 + ... + 360194354.

It is an arithmetic number, because the mean of its divisors is an integer number (720388704).

Almost surely, 2^2161166109 is an apocalyptic number.

It is an amenable number.

2161166109 is a deficient number, since it is larger than the sum of its proper divisors (720388707).

2161166109 is an equidigital number, since it uses as much as digits as its factorization.

2161166109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720388706.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 2161166109 is about 46488.3437971283. The cubic root of 2161166109 is about 1292.8933930668.

The spelling of 2161166109 in words is "two billion, one hundred sixty-one million, one hundred sixty-six thousand, one hundred nine".