12111212122111 has 2 divisors, whose sum is σ = 12111212122112. Its totient is φ = 12111212122110.

The previous prime is 12111212122103. The next prime is 12111212122153. The reversal of 12111212122111 is 11122121211121.

It is a weak prime.

It is an emirp because it is prime and its reverse (11122121211121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12111212122111 - 2³ = 12111212122103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12111212122171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6055606061055 + 6055606061056.

It is an arithmetic number, because the mean of its divisors is an integer number (6055606061056).

Almost surely, 2^{12111212122111} is an apocalyptic number.

12111212122111 is a deficient number, since it is larger than the sum of its proper divisors (1).

12111212122111 is an equidigital number, since it uses as much as digits as its factorization.

12111212122111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32, while the sum is 19.

Adding to 12111212122111 its reverse (11122121211121), we get a palindrome (23233333333232).

The spelling of 12111212122111 in words is "twelve trillion, one hundred eleven billion, two hundred twelve million, one hundred twenty-two thousand, one hundred eleven".