The formula for the volume of a cylinder is V = π r^2 h
We know what the volume (V) and PI is so:
536.94 = 3.14 r^2 h
But since we don't know the height, it is not possible to find the radius as we cannot find the value of a variable if there are still more than 1 variable in an equation in which we don't know the value of
I would suggest to delete this question and add the height or tell us the height of the cylinder in the comments