201111101221 has 2 divisors, whose sum is σ = 201111101222. Its totient is φ = 201111101220.

The previous prime is 201111101203. The next prime is 201111101237. The reversal of 201111101221 is 122101111102.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151776472225 + 49334628996 = 389585^2 + 222114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201111101221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201111101201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100555550610 + 100555550611.

It is an arithmetic number, because the mean of its divisors is an integer number (100555550611).

Almost surely, 2^201111101221 is an apocalyptic number.

It is an amenable number.

201111101221 is a deficient number, since it is larger than the sum of its proper divisors (1).

201111101221 is an equidigital number, since it uses as much as digits as its factorization.

201111101221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 201111101221 its reverse (122101111102), we get a palindrome (323212212323).

The spelling of 201111101221 in words is "two hundred one billion, one hundred eleven million, one hundred one thousand, two hundred twenty-one".