1211331111121 has 2 divisors, whose sum is σ = 1211331111122. Its totient is φ = 1211331111120.

The previous prime is 1211331111091. The next prime is 1211331111157. The reversal of 1211331111121 is 1211111331121.

It is a m-pointer prime, because the next prime (1211331111157) can be obtained adding 1211331111121 to its product of digits (36).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 876350610496 + 334980500625 = 936136^2 + 578775^2 .

It is an emirp because it is prime and its reverse (1211111331121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211331111121 - 2⁹ = 1211331110609 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211331111191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605665555560 + 605665555561.

It is an arithmetic number, because the mean of its divisors is an integer number (605665555561).

Almost surely, 2^{1211331111121} is an apocalyptic number.

It is an amenable number.

1211331111121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211331111121 is an equidigital number, since it uses as much as digits as its factorization.

1211331111121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36, while the sum is 19.

Adding to 1211331111121 its reverse (1211111331121), we get a palindrome (2422442442242).

The spelling of 1211331111121 in words is "one trillion, two hundred eleven billion, three hundred thirty-one million, one hundred eleven thousand, one hundred twenty-one".