1221222011 has 2 divisors, whose sum is σ = 1221222012. Its totient is φ = 1221222010.

The previous prime is 1221222001. The next prime is 1221222019. The reversal of 1221222011 is 1102221221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221222011 - 2¹⁴ = 1221205627 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221222019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610611005 + 610611006.

It is an arithmetic number, because the mean of its divisors is an integer number (610611006).

Almost surely, 2^1221222011 is an apocalyptic number.

1221222011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221222011 is an equidigital number, since it uses as much as digits as its factorization.

1221222011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1221222011 is about 34945.9870514484. The cubic root of 1221222011 is about 1068.8863747820.

Adding to 1221222011 its reverse (1102221221), we get a palindrome (2323443232).

The spelling of 1221222011 in words is "one billion, two hundred twenty-one million, two hundred twenty-two thousand, eleven".