1321331321 has 16 divisors (see below), whose sum is σ = 1432112640. Its totient is φ = 1216131840.

The previous prime is 1321331303. The next prime is 1321331339. The reversal of 1321331321 is 1231331231.

It is an interprime number because it is at equal distance from previous prime (1321331303) and next prime (1321331339).

It is a cyclic number.

It is not a de Polignac number, because 1321331321 - 2³⁰ = 247589497 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321331293 and 1321331302.

It is not an unprimeable number, because it can be changed into a prime (1321331521) 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 in 15 ways as a sum of consecutive naturals, for example, 49265 + ... + 71201.

It is an arithmetic number, because the mean of its divisors is an integer number (89507040).

Almost surely, 2^1321331321 is an apocalyptic number.

It is an amenable number.

1321331321 is a deficient number, since it is larger than the sum of its proper divisors (110781319).

1321331321 is a wasteful number, since it uses less digits than its factorization.

1321331321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22064.

The product of its digits is 324, while the sum is 20.

The square root of 1321331321 is about 36350.1213340478. The cubic root of 1321331321 is about 1097.3299763770.

Adding to 1321331321 its reverse (1231331231), we get a palindrome (2552662552).

The spelling of 1321331321 in words is "one billion, three hundred twenty-one million, three hundred thirty-one thousand, three hundred twenty-one".