12161818805 has 18 divisors (see below), whose sum is σ = 14737310658. Its totient is φ = 9634959840.

The previous prime is 12161818759. The next prime is 12161818811. The reversal of 12161818805 is 50881816121.

12161818805 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 158206084 + 12003612721 = 12578^2 + 109561^2 .

It is not a de Polignac number, because 12161818805 - 2¹⁰ = 12161817781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 36742490 + ... + 36742820.

It is an arithmetic number, because the mean of its divisors is an integer number (818739481).

Almost surely, 2^12161818805 is an apocalyptic number.

It is an amenable number.

12161818805 is a deficient number, since it is larger than the sum of its proper divisors (2575491853).

12161818805 is an frugal number, since it uses more digits than its factorization.

12161818805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965 (or 485 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 41.

The spelling of 12161818805 in words is "twelve billion, one hundred sixty-one million, eight hundred eighteen thousand, eight hundred five".