Hi, I'm trying to solve for the radius of the sphere.

This is the correct steps:
8.27*10^-29 = 4/3 pi * r^3
r^3 = 2.0225 * 10^-29 cu meters

When I do 8.27x10^-29 / 4/3 pi, I don't get the answer 2.0225x10^-29

Can you tell me what I'm doing wrong?

Correct, you should get

1.974*10^(-29) instead.

If you do not get the above value, it could be:
1. you did not use the correct value of pi (such as 3.14, 22/7,...)
2. Your expression is missing many parentheses. Remember PEDMAS or PEMDAS which your calculator sticks to, but it will not understand what you want to do if you made a mistake.
If you have an algebraic calculator, you would want to put in
8.27x10^(-29) / ((4/3)*π)
without missing any of the parentheses.
Use the π symbol provided with most calculators.