Talk about a brain teaser. It took Kenneth Brandon 7.5 hours to make his ways through the 66.9 quinquagintatrecentillion (which reads as "66.9 quinquaseptuagintacentilliard" in the European Union). different possible positions of his 17x17x17 Rubik's Cube. Fortunately, you can watch him wiz through it in a matter of minutes, thanks to some handy timelapse. He goes by RedKB on YouTube, and he recently uploaded a video of himself solving the cube along with a commentary on how to conquer this beast.
Brandon explains, "The way you solve a 17 by 17 is just like you would a seven by seven, or a five by five. If you can solve one of those then the 17 by 17 isn’t that hard, but it is very, very tedious. The way I'm solving it is using the 'reduction method', and basically you reduce the cube into a three by three, and then you solve the three by three."
Essentially, you start in the center and work your way out, a process that took Brandon more than 5 days. "By far, the hardest part about solving a 17 by 17 is to find the piece you're looking for. When you're looking for a little piece near the centre of the puzzle, you can easily mistake it for ones right next to it. So you have to be real careful to count, like, 'four over and six down', and make sure that you're looking for that piece."
Learn more about solving this puzzle in the video below.