201111100111991 has 2 divisors, whose sum is σ = 201111100111992. Its totient is φ = 201111100111990.

The previous prime is 201111100111981. The next prime is 201111100112057. The reversal of 201111100111991 is 199111001111102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 201111100111991 - 2¹⁰ = 201111100110967 is a prime.

It is a super-3 number, since 3×201111100111991³ (a number of 44 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201111100111931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100555550055995 + 100555550055996.

It is an arithmetic number, because the mean of its divisors is an integer number (100555550055996).

Almost surely, 2^{201111100111991} is an apocalyptic number.

201111100111991 is a deficient number, since it is larger than the sum of its proper divisors (1).

201111100111991 is an equidigital number, since it uses as much as digits as its factorization.

201111100111991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 29.

The spelling of 201111100111991 in words is "two hundred one trillion, one hundred eleven billion, one hundred million, one hundred eleven thousand, nine hundred ninety-one".