1311620408309 has 2 divisors, whose sum is σ = 1311620408310. Its totient is φ = 1311620408308.

The previous prime is 1311620408303. The next prime is 1311620408317. The reversal of 1311620408309 is 9038040261131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 999156178084 + 312464230225 = 999578^2 + 558985^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311620408309 - 2⁸ = 1311620408053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311620408303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655810204154 + 655810204155.

It is an arithmetic number, because the mean of its divisors is an integer number (655810204155).

Almost surely, 2^{1311620408309} is an apocalyptic number.

It is an amenable number.

1311620408309 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311620408309 is an equidigital number, since it uses as much as digits as its factorization.

1311620408309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The spelling of 1311620408309 in words is "one trillion, three hundred eleven billion, six hundred twenty million, four hundred eight thousand, three hundred nine".