1311320191 has 2 divisors, whose sum is σ = 1311320192. Its totient is φ = 1311320190.

The previous prime is 1311320099. The next prime is 1311320267. The reversal of 1311320191 is 1910231131.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1311320191 - 2⁹ = 1311319679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311320291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655660095 + 655660096.

It is an arithmetic number, because the mean of its divisors is an integer number (655660096).

Almost surely, 2^1311320191 is an apocalyptic number.

1311320191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311320191 is an equidigital number, since it uses as much as digits as its factorization.

1311320191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 22.

The square root of 1311320191 is about 36212.1552934923. The cubic root of 1311320191 is about 1094.5516233797.

The spelling of 1311320191 in words is "one billion, three hundred eleven million, three hundred twenty thousand, one hundred ninety-one".