1991492919011 has 2 divisors, whose sum is σ = 1991492919012. Its totient is φ = 1991492919010.

The previous prime is 1991492919007. The next prime is 1991492919047. The reversal of 1991492919011 is 1109192941991.

It is a weak prime.

It is an emirp because it is prime and its reverse (1109192941991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1991492919011 - 2² = 1991492919007 is a prime.

It is not a weakly prime, because it can be changed into another prime (1991492915011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995746459505 + 995746459506.

It is an arithmetic number, because the mean of its divisors is an integer number (995746459506).

Almost surely, 2^{1991492919011} is an apocalyptic number.

1991492919011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1991492919011 is an equidigital number, since it uses as much as digits as its factorization.

1991492919011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 472392, while the sum is 56.

The spelling of 1991492919011 in words is "one trillion, nine hundred ninety-one billion, four hundred ninety-two million, nine hundred nineteen thousand, eleven".