311380561 has 2 divisors, whose sum is σ = 311380562. Its totient is φ = 311380560.

The previous prime is 311380549. The next prime is 311380571. The reversal of 311380561 is 165083113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 297355536 + 14025025 = 17244^2 + 3745^2 .

It is a cyclic number.

It is not a de Polignac number, because 311380561 - 2¹¹ = 311378513 is a prime.

It is not a weakly prime, because it can be changed into another prime (311380571) 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, 155690280 + 155690281.

It is an arithmetic number, because the mean of its divisors is an integer number (155690281).

Almost surely, 2^311380561 is an apocalyptic number.

It is an amenable number.

311380561 is a deficient number, since it is larger than the sum of its proper divisors (1).

311380561 is an equidigital number, since it uses as much as digits as its factorization.

311380561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 311380561 is about 17645.9786070368. The cubic root of 311380561 is about 677.7931346805.

The spelling of 311380561 in words is "three hundred eleven million, three hundred eighty thousand, five hundred sixty-one".