13221221431321 has 4 divisors (see below), whose sum is σ = 13221241561444. Its totient is φ = 13221201301200.

The previous prime is 13221221431307. The next prime is 13221221431343. The reversal of 13221221431321 is 12313412212231.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4315025725696 + 8906195705625 = 2077264^2 + 2984325^2 .

It is a cyclic number.

It is not a de Polignac number, because 13221221431321 - 2⁷ = 13221221431193 is a prime.

It is a super-2 number, since 2×13221221431321² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13221221431321.

It is not an unprimeable number, because it can be changed into a prime (13221221431351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9045450 + ... + 10404931.

It is an arithmetic number, because the mean of its divisors is an integer number (3305310390361).

Almost surely, 2^{13221221431321} is an apocalyptic number.

It is an amenable number.

13221221431321 is a deficient number, since it is larger than the sum of its proper divisors (20130123).

13221221431321 is an equidigital number, since it uses as much as digits as its factorization.

13221221431321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20130122.

The product of its digits is 3456, while the sum is 28.

Adding to 13221221431321 its reverse (12313412212231), we get a palindrome (25534633643552).

The spelling of 13221221431321 in words is "thirteen trillion, two hundred twenty-one billion, two hundred twenty-one million, four hundred thirty-one thousand, three hundred twenty-one".