1211211212011 has 2 divisors, whose sum is σ = 1211211212012. Its totient is φ = 1211211212010.

The previous prime is 1211211212009. The next prime is 1211211212017. The reversal of 1211211212011 is 1102121121121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1211211212011 - 2¹ = 1211211212009 is a prime.

Together with 1211211212009, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1211211212017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605605606005 + 605605606006.

It is an arithmetic number, because the mean of its divisors is an integer number (605605606006).

Almost surely, 2^{1211211212011} is an apocalyptic number.

1211211212011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211211212011 is an equidigital number, since it uses as much as digits as its factorization.

1211211212011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 1211211212011 its reverse (1102121121121), we get a palindrome (2313332333132).

The spelling of 1211211212011 in words is "one trillion, two hundred eleven billion, two hundred eleven million, two hundred twelve thousand, eleven".