1311323111 has 4 divisors (see below), whose sum is σ = 1498654992. Its totient is φ = 1123991232.

The previous prime is 1311323093. The next prime is 1311323113. The reversal of 1311323111 is 1113231131.

It is a semiprime because it is the product of two primes.

It is a de Polignac number, because none of the positive numbers 2^k-1311323111 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311323111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311323113) 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 in 3 ways as a sum of consecutive naturals, for example, 93665930 + ... + 93665943.

It is an arithmetic number, because the mean of its divisors is an integer number (374663748).

Almost surely, 2^1311323111 is an apocalyptic number.

1311323111 is a deficient number, since it is larger than the sum of its proper divisors (187331881).

1311323111 is an equidigital number, since it uses as much as digits as its factorization.

1311323111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187331880.

The product of its digits is 54, while the sum is 17.

The square root of 1311323111 is about 36212.1956114235. The cubic root of 1311323111 is about 1094.5524358150.

Adding to 1311323111 its reverse (1113231131), we get a palindrome (2424554242).

The spelling of 1311323111 in words is "one billion, three hundred eleven million, three hundred twenty-three thousand, one hundred eleven".