12111111111111 has 16 divisors (see below), whose sum is σ = 16152309196800. Its totient is φ = 8071993821888.

The previous prime is 12111111111083. The next prime is 12111111111139. The reversal of 12111111111111 is 11111111111121.

It is an interprime number because it is at equal distance from previous prime (12111111111083) and next prime (12111111111139).

It is not a de Polignac number, because 12111111111111 - 2¹⁷ = 12111110980039 is a prime.

12111111111111 is a modest number, since divided by 11111111 gives 121111 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12111111115111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 251311560 + ... + 251359746.

It is an arithmetic number, because the mean of its divisors is an integer number (1009519324800).

Almost surely, 2^{12111111111111} is an apocalyptic number.

12111111111111 is a deficient number, since it is larger than the sum of its proper divisors (4041198085689).

12111111111111 is a wasteful number, since it uses less digits than its factorization.

12111111111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68038.

The product of its digits is 2, while the sum is 15.

Adding to 12111111111111 its reverse (11111111111121), we get a palindrome (23222222222232).

It can be divided in two parts, 121 and 11111111111, that multiplied together give a palindrome (1344444444431).

The spelling of 12111111111111 in words is "twelve trillion, one hundred eleven billion, one hundred eleven million, one hundred eleven thousand, one hundred eleven".