1211222111611 has 2 divisors, whose sum is σ = 1211222111612. Its totient is φ = 1211222111610.

The previous prime is 1211222111557. The next prime is 1211222111707. The reversal of 1211222111611 is 1161112221121.

It is a m-pointer prime, because the next prime (1211222111707) can be obtained adding 1211222111611 to its product of digits (96).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1211222111611 - 2¹¹ = 1211222109563 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211222111711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605611055805 + 605611055806.

It is an arithmetic number, because the mean of its divisors is an integer number (605611055806).

Almost surely, 2^{1211222111611} is an apocalyptic number.

1211222111611 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211222111611 is an equidigital number, since it uses as much as digits as its factorization.

1211222111611 is an odious number, because the sum of its binary digits is odd.

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

Adding to 1211222111611 its reverse (1161112221121), we get a palindrome (2372334332732).

The spelling of 1211222111611 in words is "one trillion, two hundred eleven billion, two hundred twenty-two million, one hundred eleven thousand, six hundred eleven".