1331311321 has 2 divisors, whose sum is σ = 1331311322. Its totient is φ = 1331311320.

The previous prime is 1331311309. The next prime is 1331311343. The reversal of 1331311321 is 1231131331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1105230025 + 226081296 = 33245^2 + 15036^2 .

It is an emirp because it is prime and its reverse (1231131331) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1331311321 - 2⁷ = 1331311193 is a prime.

It is not a weakly prime, because it can be changed into another prime (1331311301) 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, 665655660 + 665655661.

It is an arithmetic number, because the mean of its divisors is an integer number (665655661).

Almost surely, 2^1331311321 is an apocalyptic number.

It is an amenable number.

1331311321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331311321 is an equidigital number, since it uses as much as digits as its factorization.

1331311321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162, while the sum is 19.

The square root of 1331311321 is about 36487.1391177768. The cubic root of 1331311321 is about 1100.0857566751.

Adding to 1331311321 its reverse (1231131331), we get a palindrome (2562442652).

The spelling of 1331311321 in words is "one billion, three hundred thirty-one million, three hundred eleven thousand, three hundred twenty-one".