311426821 has 2 divisors, whose sum is σ = 311426822. Its totient is φ = 311426820.

The previous prime is 311426807. The next prime is 311426851. The reversal of 311426821 is 128624113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 192376900 + 119049921 = 13870^2 + 10911^2 .

It is an emirp because it is prime and its reverse (128624113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 311426821 - 2⁵ = 311426789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 311426821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311426851) 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 as a sum of consecutive naturals, namely, 155713410 + 155713411.

It is an arithmetic number, because the mean of its divisors is an integer number (155713411).

Almost surely, 2^311426821 is an apocalyptic number.

It is an amenable number.

311426821 is a deficient number, since it is larger than the sum of its proper divisors (1).

311426821 is an equidigital number, since it uses as much as digits as its factorization.

311426821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 28.

The square root of 311426821 is about 17647.2893385925. The cubic root of 311426821 is about 677.8266982805.

The spelling of 311426821 in words is "three hundred eleven million, four hundred twenty-six thousand, eight hundred twenty-one".