311243321 has 2 divisors, whose sum is σ = 311243322. Its totient is φ = 311243320.

The previous prime is 311243281. The next prime is 311243323. The reversal of 311243321 is 123342113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 186049600 + 125193721 = 13640^2 + 11189^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311243321 is a prime.

Together with 311243323, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 311243293 and 311243302.

It is not a weakly prime, because it can be changed into another prime (311243323) 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 as a sum of consecutive naturals, namely, 155621660 + 155621661.

It is an arithmetic number, because the mean of its divisors is an integer number (155621661).

Almost surely, 2^311243321 is an apocalyptic number.

It is an amenable number.

311243321 is a deficient number, since it is larger than the sum of its proper divisors (1).

311243321 is an equidigital number, since it uses as much as digits as its factorization.

311243321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 20.

The square root of 311243321 is about 17642.0894737557. The cubic root of 311243321 is about 677.6935416519.

Adding to 311243321 its reverse (123342113), we get a palindrome (434585434).

The spelling of 311243321 in words is "three hundred eleven million, two hundred forty-three thousand, three hundred twenty-one".