1323111221 has 2 divisors, whose sum is σ = 1323111222. Its totient is φ = 1323111220.

The previous prime is 1323111191. The next prime is 1323111253. The reversal of 1323111221 is 1221113231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1318488721 + 4622500 = 36311^2 + 2150^2 .

It is a cyclic number.

It is not a de Polignac number, because 1323111221 - 2²⁶ = 1256002357 is a prime.

It is a super-2 number, since 2×1323111221² = 3501246606272221682, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1323111221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1323111821) 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, 661555610 + 661555611.

It is an arithmetic number, because the mean of its divisors is an integer number (661555611).

Almost surely, 2^1323111221 is an apocalyptic number.

It is an amenable number.

1323111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1323111221 is an equidigital number, since it uses as much as digits as its factorization.

1323111221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 17.

The square root of 1323111221 is about 36374.5958190603. The cubic root of 1323111221 is about 1097.8224749295.

Adding to 1323111221 its reverse (1221113231), we get a palindrome (2544224452).

The spelling of 1323111221 in words is "one billion, three hundred twenty-three million, one hundred eleven thousand, two hundred twenty-one".