Very very roughly, an Earth month.
The Sun isn't solid, so it doesn't all have to rotate at the same rate. Different latitudes actually rotate at different speeds. One complete rotation is about 24 days at the Sun's equator, but 35 days near the poles !
True, but only if the temperature of the gas doesn't change ...
which is pretty hard to manage when you're compressing it.
I think Boyle's law actually says something like
(pressure) x (volume) / (temperature) = constant.
So you can see that if you want to say anything about two of the
quantities, you always have to stipulate that the statement is true
as long as the third one doesn't change.
If the Sun were to turn into a black hole, or be replaced by a black hole
with the same mass as the Sun, then Earth would continue to orbit it
as usual. (But it would be very cold and dark around here.)
