11111001211091 has 4 divisors (see below), whose sum is σ = 11111010860592. Its totient is φ = 11110991561592.

The previous prime is 11111001211087. The next prime is 11111001211097. The reversal of 11111001211091 is 19011210011111.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 11111001211091 - 2² = 11111001211087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11111001211097) 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 in 3 ways as a sum of consecutive naturals, for example, 2819855 + ... + 5493048.

It is an arithmetic number, because the mean of its divisors is an integer number (2777752715148).

Almost surely, 2^{11111001211091} is an apocalyptic number.

11111001211091 is a deficient number, since it is larger than the sum of its proper divisors (9649501).

11111001211091 is an equidigital number, since it uses as much as digits as its factorization.

11111001211091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9649500.

The product of its (nonzero) digits is 18, while the sum is 20.

The spelling of 11111001211091 in words is "eleven trillion, one hundred eleven billion, one million, two hundred eleven thousand, ninety-one".