ErieQuiet asked if the 20 could be fixed, so I took the original file from aveday_ and used tinkercad to add numbers of my own.
My Ender 3 Pro did a great job, and I printed it at 200% and each triangle measures 2 1/2" on each side and the die is about the size of a softball. I use a pane of glass as a bed surface, that is why the surface of the faces are so smooth.
As noted by aveday_ : "Snapping them together one-by-one would be near impossible, as the final piece doesn't have enough clearance; I recommend constructing two 5-sided pyramids and snapping those on to either side of a ring of 10" (see photos on his original page).
It took me quite a bit of force to get the die together. The design allows you to position each triangle face in whichever configuration you want. I used Dice Lab's (https://www.mathartfun.com/DiceLabDice.html) pattern for a numerically-balanced d20. I built the die from one vertex and then added the final "top" consisting of 5 triangles.