991101221110111 has 2 divisors, whose sum is σ = 991101221110112. Its totient is φ = 991101221110110.

The previous prime is 991101221110069. The next prime is 991101221110141. The reversal of 991101221110111 is 111011122101199.

991101221110111 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (111011122101199) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 991101221110111 - 2¹⁹ = 991101220585823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991101221110141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495550610555055 + 495550610555056.

It is an arithmetic number, because the mean of its divisors is an integer number (495550610555056).

Almost surely, 2^{991101221110111} is an apocalyptic number.

991101221110111 is a deficient number, since it is larger than the sum of its proper divisors (1).

991101221110111 is an equidigital number, since it uses as much as digits as its factorization.

991101221110111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 31.

The spelling of 991101221110111 in words is "nine hundred ninety-one trillion, one hundred one billion, two hundred twenty-one million, one hundred ten thousand, one hundred eleven".