1311123331321 has 2 divisors, whose sum is σ = 1311123331322. Its totient is φ = 1311123331320.

The previous prime is 1311123331211. The next prime is 1311123331333. The reversal of 1311123331321 is 1231333211131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1038676914025 + 272446417296 = 1019155^2 + 521964^2 .

It is an emirp because it is prime and its reverse (1231333211131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1311123331321 - 2¹⁵ = 1311123298553 is a prime.

It is not a weakly prime, because it can be changed into another prime (1311123331351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655561665660 + 655561665661.

It is an arithmetic number, because the mean of its divisors is an integer number (655561665661).

Almost surely, 2^{1311123331321} is an apocalyptic number.

It is an amenable number.

1311123331321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311123331321 is an equidigital number, since it uses as much as digits as its factorization.

1311123331321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 972, while the sum is 25.

Adding to 1311123331321 its reverse (1231333211131), we get a palindrome (2542456542452).

The spelling of 1311123331321 in words is "one trillion, three hundred eleven billion, one hundred twenty-three million, three hundred thirty-one thousand, three hundred twenty-one".