11121011112221 has 2 divisors, whose sum is σ = 11121011112222. Its totient is φ = 11121011112220.

The previous prime is 11121011112209. The next prime is 11121011112223. The reversal of 11121011112221 is 12221111012111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8928227664196 + 2192783448025 = 2988014^2 + 1480805^2 .

It is an emirp because it is prime and its reverse (12221111012111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11121011112221 - 2¹⁸ = 11121010850077 is a prime.

Together with 11121011112223, 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 11121011112221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11121011112223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5560505556110 + 5560505556111.

It is an arithmetic number, because the mean of its divisors is an integer number (5560505556111).

Almost surely, 2^{11121011112221} is an apocalyptic number.

It is an amenable number.

11121011112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11121011112221 is an equidigital number, since it uses as much as digits as its factorization.

11121011112221 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 17.

Adding to 11121011112221 its reverse (12221111012111), we get a palindrome (23342122124332).

The spelling of 11121011112221 in words is "eleven trillion, one hundred twenty-one billion, eleven million, one hundred twelve thousand, two hundred twenty-one".