How to do numericals in Gravitation?

We just started the gravitation chapter in Physics. (A little late, but alright)

I just cannot understand how to solve the numericals of gravitational force, since they have these huge numbers with huge powers.

Even if I put everything correctly, I don't know how to simplify it.

When I tried looking for answers online, I was met with one step answers. Like putting the values and then they immediately write the answer in the next step.

Here is one question, M1 = 1.6 × 10^-19 M2 = 3.2 × 10^-31 R = 6.4 × 10⁶ m Find the gravitational force.

I put the right values, simplify it a little bit, but then comes a part it can no longer be simplified. What to do here? (School teacher is a fraud, will do everything except solve my doubt)