2001111123811 has 2 divisors, whose sum is σ = 2001111123812. Its totient is φ = 2001111123810.

The previous prime is 2001111123751. The next prime is 2001111123827. The reversal of 2001111123811 is 1183211111002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001111123811 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001111123841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000555561905 + 1000555561906.

It is an arithmetic number, because the mean of its divisors is an integer number (1000555561906).

Almost surely, 2^{2001111123811} is an apocalyptic number.

2001111123811 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001111123811 is an equidigital number, since it uses as much as digits as its factorization.

2001111123811 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 22.

Adding to 2001111123811 its reverse (1183211111002), we get a palindrome (3184322234813).

The spelling of 2001111123811 in words is "two trillion, one billion, one hundred eleven million, one hundred twenty-three thousand, eight hundred eleven".