111001011010991 has 2 divisors, whose sum is σ = 111001011010992. Its totient is φ = 111001011010990.

The previous prime is 111001011010979. The next prime is 111001011011071. The reversal of 111001011010991 is 199010110100111.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111001011010991 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111001011010991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111001011010931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55500505505495 + 55500505505496.

It is an arithmetic number, because the mean of its divisors is an integer number (55500505505496).

Almost surely, 2^{111001011010991} is an apocalyptic number.

111001011010991 is a deficient number, since it is larger than the sum of its proper divisors (1).

111001011010991 is an equidigital number, since it uses as much as digits as its factorization.

111001011010991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81, while the sum is 26.

The spelling of 111001011010991 in words is "one hundred eleven trillion, one billion, eleven million, ten thousand, nine hundred ninety-one".