1211211111311 has 2 divisors, whose sum is σ = 1211211111312. Its totient is φ = 1211211111310.

The previous prime is 1211211111289. The next prime is 1211211111323. The reversal of 1211211111311 is 1131111121121.

It is a m-pointer prime, because the next prime (1211211111323) can be obtained adding 1211211111311 to its product of digits (12).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1211211111311 - 2²² = 1211206917007 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211211111311.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211211111371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605605555655 + 605605555656.

It is an arithmetic number, because the mean of its divisors is an integer number (605605555656).

Almost surely, 2^{1211211111311} is an apocalyptic number.

1211211111311 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211211111311 is an equidigital number, since it uses as much as digits as its factorization.

1211211111311 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12, while the sum is 17.

Adding to 1211211111311 its reverse (1131111121121), we get a palindrome (2342322232432).

The spelling of 1211211111311 in words is "one trillion, two hundred eleven billion, two hundred eleven million, one hundred eleven thousand, three hundred eleven".