12166111655 has 4 divisors (see below), whose sum is σ = 14599333992. Its totient is φ = 9732889320.

The previous prime is 12166111621. The next prime is 12166111679. The reversal of 12166111655 is 55611166121.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-12166111655 is a prime.

It is a Duffinian number.

It is a congruent 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, 1216611161 + ... + 1216611170.

It is an arithmetic number, because the mean of its divisors is an integer number (3649833498).

Almost surely, 2^12166111655 is an apocalyptic number.

12166111655 is a deficient number, since it is larger than the sum of its proper divisors (2433222337).

12166111655 is an equidigital number, since it uses as much as digits as its factorization.

12166111655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2433222336.

The product of its digits is 10800, while the sum is 35.

Adding to 12166111655 its reverse (55611166121), we get a palindrome (67777277776).

The spelling of 12166111655 in words is "twelve billion, one hundred sixty-six million, one hundred eleven thousand, six hundred fifty-five".