11220121211111 has 2 divisors, whose sum is σ = 11220121211112. Its totient is φ = 11220121211110.

The previous prime is 11220121211107. The next prime is 11220121211113. The reversal of 11220121211111 is 11111212102211.

11220121211111 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11220121211111 - 2² = 11220121211107 is a prime.

It is a super-2 number, since 2×11220121211111² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 11220121211113, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11220121211111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11220121211113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5610060605555 + 5610060605556.

It is an arithmetic number, because the mean of its divisors is an integer number (5610060605556).

Almost surely, 2^{11220121211111} is an apocalyptic number.

11220121211111 is a deficient number, since it is larger than the sum of its proper divisors (1).

11220121211111 is an equidigital number, since it uses as much as digits as its factorization.

11220121211111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 11220121211111 its reverse (11111212102211), we get a palindrome (22331333313322).

The spelling of 11220121211111 in words is "eleven trillion, two hundred twenty billion, one hundred twenty-one million, two hundred eleven thousand, one hundred eleven".