The 33x33x33 is, as of the time of this writing (April 14, 2018) the highest fully functional physical puzzle cube. It was created by Grégoire Pfennig, who presented it on his YouTube channel Greg's Puzzles.
The puzzle is a testament to the great patience of it's creator, as it took Grégoire 205 hours to make, according to the video. It is uncertain whether this refers to the time it took to 3D print, to assemble by hand, or 3D print in union with an assembling by hand, but it is likely the latter. The cube has 6,153 components, 6,534 stickers, and each layer except for the outermost layers have a thickness of just 4.1 mm.