I found an issue in my calculation. If you filled up the non-glitchy area of Slate with 1x1 bricks, you would have ~6399961600096 * 1037 bricks3.
That's approximately 63999616000960000000000000000 000000000000000000000 bricks3.
Where the hell are you getting that from?
There is a total flat surface area of 205520896 bricks, multiplied by height
The height is 19999980 TU multiplied by 6 (1 TU = 2 studs = 6 plates), which is 119999880.
So that's 205520896 multiplied by 119999880, which comes out to be 24,662,482,857,492,480.