11611111121111 has 2 divisors, whose sum is σ = 11611111121112. Its totient is φ = 11611111121110.

The previous prime is 11611111121089. The next prime is 11611111121123. The reversal of 11611111121111 is 11112111111611.

It is a m-pointer prime, because the next prime (11611111121123) can be obtained adding 11611111121111 to its product of digits (12).

It is a strong prime.

It is an emirp because it is prime and its reverse (11112111111611) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11611111121111 - 2¹⁴ = 11611111104727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11611111121191) 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 as a sum of consecutive naturals, namely, 5805555560555 + 5805555560556.

It is an arithmetic number, because the mean of its divisors is an integer number (5805555560556).

Almost surely, 2^{11611111121111} is an apocalyptic number.

11611111121111 is a deficient number, since it is larger than the sum of its proper divisors (1).

11611111121111 is an equidigital number, since it uses as much as digits as its factorization.

11611111121111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12, while the sum is 20.

Adding to 11611111121111 its reverse (11112111111611), we get a palindrome (22723222232722).

The spelling of 11611111121111 in words is "eleven trillion, six hundred eleven billion, one hundred eleven million, one hundred twenty-one thousand, one hundred eleven".