1121211210221 has 2 divisors, whose sum is σ = 1121211210222. Its totient is φ = 1121211210220.

The previous prime is 1121211210181. The next prime is 1121211210227. The reversal of 1121211210221 is 1220121121211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1072198120900 + 49013089321 = 1035470^2 + 221389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1121211210221 is a prime.

It is a super-2 number, since 2×1121211210221² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1121211210221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1121211210227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 560605605110 + 560605605111.

It is an arithmetic number, because the mean of its divisors is an integer number (560605605111).

Almost surely, 2^{1121211210221} is an apocalyptic number.

It is an amenable number.

1121211210221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1121211210221 is an equidigital number, since it uses as much as digits as its factorization.

1121211210221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1121211210221 its reverse (1220121121211), we get a palindrome (2341332331432).

The spelling of 1121211210221 in words is "one trillion, one hundred twenty-one billion, two hundred eleven million, two hundred ten thousand, two hundred twenty-one".