311020643 has 2 divisors, whose sum is σ = 311020644. Its totient is φ = 311020642.

The previous prime is 311020637. The next prime is 311020657. The reversal of 311020643 is 346020113.

It is a weak prime.

It is an emirp because it is prime and its reverse (346020113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 311020643 - 2⁶ = 311020579 is a prime.

It is not a weakly prime, because it can be changed into another prime (311020673) 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, 155510321 + 155510322.

It is an arithmetic number, because the mean of its divisors is an integer number (155510322).

Almost surely, 2^311020643 is an apocalyptic number.

311020643 is a deficient number, since it is larger than the sum of its proper divisors (1).

311020643 is an equidigital number, since it uses as much as digits as its factorization.

311020643 is an odious number, because the sum of its binary digits is odd.

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

The square root of 311020643 is about 17635.7773574062. Note that the first 3 decimals coincide. The cubic root of 311020643 is about 677.5318852293.

Adding to 311020643 its reverse (346020113), we get a palindrome (657040756).

The spelling of 311020643 in words is "three hundred eleven million, twenty thousand, six hundred forty-three".