211131611111 has 2 divisors, whose sum is σ = 211131611112. Its totient is φ = 211131611110.

The previous prime is 211131611071. The next prime is 211131611147. The reversal of 211131611111 is 111116131112.

It is a m-pointer prime, because the next prime (211131611147) can be obtained adding 211131611111 to its product of digits (36).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211131611111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211131611161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105565805555 + 105565805556.

It is an arithmetic number, because the mean of its divisors is an integer number (105565805556).

Almost surely, 2^211131611111 is an apocalyptic number.

211131611111 is a deficient number, since it is larger than the sum of its proper divisors (1).

211131611111 is an equidigital number, since it uses as much as digits as its factorization.

211131611111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36, while the sum is 20.

Adding to 211131611111 its reverse (111116131112), we get a palindrome (322247742223).

The spelling of 211131611111 in words is "two hundred eleven billion, one hundred thirty-one million, six hundred eleven thousand, one hundred eleven".