90,525,801,730 Cannon Balls
Matt Parker has a new favourite number - again!
Some notes from Matt on how far he has investigated: https://www.numberphile.com/cannon-ball-numbers
Matt's book "Humble Pi" via Maths Gear (signed and ships almost everywhere): http://bit.ly/Humble_Pi
More Numberphile videos with Matt: http://bit.ly/Matt_Videos
James Grime sphere packing: https://youtu.be/CROeIGfr3gs
Lucas Numbers: https://youtu.be/PeUbRXnbmms