11012121221 has 2 divisors, whose sum is σ = 11012121222. Its totient is φ = 11012121220.

The previous prime is 11012121199. The next prime is 11012121223. The reversal of 11012121221 is 12212121011.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6318501121 + 4693620100 = 79489^2 + 68510^2 .

It is an emirp because it is prime and its reverse (12212121011) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11012121221 - 2⁶ = 11012121157 is a prime.

Together with 11012121223, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 11012121196 and 11012121205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11012121223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5506060610 + 5506060611.

It is an arithmetic number, because the mean of its divisors is an integer number (5506060611).

Almost surely, 2^11012121221 is an apocalyptic number.

It is an amenable number.

11012121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11012121221 is an equidigital number, since it uses as much as digits as its factorization.

11012121221 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 14.

Adding to 11012121221 its reverse (12212121011), we get a palindrome (23224242232).

The spelling of 11012121221 in words is "eleven billion, twelve million, one hundred twenty-one thousand, two hundred twenty-one".