1211342221 has 2 divisors, whose sum is σ = 1211342222. Its totient is φ = 1211342220.

The previous prime is 1211342213. The next prime is 1211342227. The reversal of 1211342221 is 1222431121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1198128996 + 13213225 = 34614^2 + 3635^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211342221 - 2³ = 1211342213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211342227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605671110 + 605671111.

It is an arithmetic number, because the mean of its divisors is an integer number (605671111).

Almost surely, 2^1211342221 is an apocalyptic number.

It is an amenable number.

1211342221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211342221 is an equidigital number, since it uses as much as digits as its factorization.

1211342221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 192, while the sum is 19.

The square root of 1211342221 is about 34804.3419848731. The cubic root of 1211342221 is about 1065.9961059596.

Adding to 1211342221 its reverse (1222431121), we get a palindrome (2433773342).

Subtracting 1211342221 from its reverse (1222431121), we obtain a square (11088900 = 3330²).

The spelling of 1211342221 in words is "one billion, two hundred eleven million, three hundred forty-two thousand, two hundred twenty-one".