2011221209791 has 2 divisors, whose sum is σ = 2011221209792. Its totient is φ = 2011221209790.

The previous prime is 2011221209773. The next prime is 2011221209831. The reversal of 2011221209791 is 1979021221102.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2011221209791 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2011221209791.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011221209731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005610604895 + 1005610604896.

It is an arithmetic number, because the mean of its divisors is an integer number (1005610604896).

Almost surely, 2^{2011221209791} is an apocalyptic number.

2011221209791 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011221209791 is an equidigital number, since it uses as much as digits as its factorization.

2011221209791 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 37.

The spelling of 2011221209791 in words is "two trillion, eleven billion, two hundred twenty-one million, two hundred nine thousand, seven hundred ninety-one".