1311235133521 has 2 divisors, whose sum is σ = 1311235133522. Its totient is φ = 1311235133520.

The previous prime is 1311235133449. The next prime is 1311235133563. The reversal of 1311235133521 is 1253315321131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1275180719121 + 36054414400 = 1129239^2 + 189880^2 .

It is an emirp because it is prime and its reverse (1253315321131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1311235133521 - 2¹⁵ = 1311235100753 is a prime.

It is not a weakly prime, because it can be changed into another prime (1311235833521) 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, 655617566760 + 655617566761.

It is an arithmetic number, because the mean of its divisors is an integer number (655617566761).

Almost surely, 2^{1311235133521} is an apocalyptic number.

It is an amenable number.

1311235133521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311235133521 is an equidigital number, since it uses as much as digits as its factorization.

1311235133521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8100, while the sum is 31.

The spelling of 1311235133521 in words is "one trillion, three hundred eleven billion, two hundred thirty-five million, one hundred thirty-three thousand, five hundred twenty-one".