311321 has 4 divisors (see below), whose sum is σ = 329652. Its totient is φ = 292992.

The previous prime is 311303. The next prime is 311323. The reversal of 311321 is 123113.

311321 is nontrivially palindromic in base 2.

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 160000 + 151321 = 400^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 311321 - 2¹⁸ = 49177 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 311321.

It is not an unprimeable number, because it can be changed into a prime (311323) 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, 9140 + ... + 9173.

It is an arithmetic number, because the mean of its divisors is an integer number (82413).

2³¹¹³²¹ is an apocalyptic number.

It is an amenable number.

311321 is a deficient number, since it is larger than the sum of its proper divisors (18331).

311321 is a wasteful number, since it uses less digits than its factorization.

311321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18330.

The product of its digits is 18, while the sum is 11.

The square root of 311321 is about 557.9614682037. The cubic root of 311321 is about 67.7749915743.

Adding to 311321 its reverse (123113), we get a palindrome (434434).

The spelling of 311321 in words is "three hundred eleven thousand, three hundred twenty-one", and thus it is an iban number.