1311331313 has 4 divisors (see below), whose sum is σ = 1311567348. Its totient is φ = 1311095280.

The previous prime is 1311331297. The next prime is 1311331321. The reversal of 1311331313 is 3131331131.

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

It can be written as a sum of positive squares in 2 ways, for example, as 807014464 + 504316849 = 28408^2 + 22457^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311331313 - 2⁴ = 1311331297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311331013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109478 + ... + 120863.

It is an arithmetic number, because the mean of its divisors is an integer number (327891837).

Almost surely, 2^1311331313 is an apocalyptic number.

It is an amenable number.

1311331313 is a deficient number, since it is larger than the sum of its proper divisors (236035).

1311331313 is an equidigital number, since it uses as much as digits as its factorization.

1311331313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236034.

The product of its digits is 243, while the sum is 20.

The square root of 1311331313 is about 36212.3088603861. The cubic root of 1311331313 is about 1094.5547178613.

Adding to 1311331313 its reverse (3131331131), we get a palindrome (4442662444).

The spelling of 1311331313 in words is "one billion, three hundred eleven million, three hundred thirty-one thousand, three hundred thirteen".