1323212221 has 6 divisors (see below), whose sum is σ = 1405627130. Its totient is φ = 1245375936.

The previous prime is 1323212173. The next prime is 1323212237. The reversal of 1323212221 is 1222123231.

It can be written as a sum of positive squares in 3 ways, for example, as 938503225 + 384708996 = 30635^2 + 19614^2 .

It is not a de Polignac number, because 1323212221 - 2²¹ = 1321115069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1323212251) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2289006 + ... + 2289583.

Almost surely, 2^1323212221 is an apocalyptic number.

It is an amenable number.

1323212221 is a deficient number, since it is larger than the sum of its proper divisors (82414909).

1323212221 is an equidigital number, since it uses as much as digits as its factorization.

1323212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4578623 (or 4578606 counting only the distinct ones).

The product of its digits is 288, while the sum is 19.

The square root of 1323212221 is about 36375.9841241443. The cubic root of 1323212221 is about 1097.8504083960.

Adding to 1323212221 its reverse (1222123231), we get a palindrome (2545335452).

The spelling of 1323212221 in words is "one billion, three hundred twenty-three million, two hundred twelve thousand, two hundred twenty-one".