311531313 has 4 divisors (see below), whose sum is σ = 415375088. Its totient is φ = 207687540.

The previous prime is 311531303. The next prime is 311531317. The reversal of 311531313 is 313135113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 311531313 - 2⁸ = 311531057 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 311531313.

It is not an unprimeable number, because it can be changed into a prime (311531317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51921883 + ... + 51921888.

It is an arithmetic number, because the mean of its divisors is an integer number (103843772).

Almost surely, 2^311531313 is an apocalyptic number.

It is an amenable number.

311531313 is a deficient number, since it is larger than the sum of its proper divisors (103843775).

311531313 is a wasteful number, since it uses less digits than its factorization.

311531313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103843774.

The product of its digits is 405, while the sum is 21.

The square root of 311531313 is about 17650.2496582910. The cubic root of 311531313 is about 677.9024994453.

Adding to 311531313 its reverse (313135113), we get a palindrome (624666426).

The spelling of 311531313 in words is "three hundred eleven million, five hundred thirty-one thousand, three hundred thirteen".