1311423661021 has 2 divisors, whose sum is σ = 1311423661022. Its totient is φ = 1311423661020.

The previous prime is 1311423661007. The next prime is 1311423661043. The reversal of 1311423661021 is 1201663241131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1190093355396 + 121330305625 = 1090914^2 + 348325^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311423661021 - 2¹¹ = 1311423658973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311423061021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655711830510 + 655711830511.

It is an arithmetic number, because the mean of its divisors is an integer number (655711830511).

Almost surely, 2^{1311423661021} is an apocalyptic number.

It is an amenable number.

1311423661021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311423661021 is an equidigital number, since it uses as much as digits as its factorization.

1311423661021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 1311423661021 in words is "one trillion, three hundred eleven billion, four hundred twenty-three million, six hundred sixty-one thousand, twenty-one".