1320311221 has 2 divisors, whose sum is σ = 1320311222. Its totient is φ = 1320311220.

The previous prime is 1320311203. The next prime is 1320311227. The reversal of 1320311221 is 1221130231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1318488721 + 1822500 = 36311^2 + 1350^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320311221 - 2⁷ = 1320311093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1320311195 and 1320311204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1320311227) 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, 660155610 + 660155611.

It is an arithmetic number, because the mean of its divisors is an integer number (660155611).

Almost surely, 2^1320311221 is an apocalyptic number.

It is an amenable number.

1320311221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320311221 is an equidigital number, since it uses as much as digits as its factorization.

1320311221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1320311221 is about 36336.0870347923. The cubic root of 1320311221 is about 1097.0475151756.

Adding to 1320311221 its reverse (1221130231), we get a palindrome (2541441452).

The spelling of 1320311221 in words is "one billion, three hundred twenty million, three hundred eleven thousand, two hundred twenty-one".