Amazing 276

Ben Sparks discusses aliquot sequences and why 276 holds a surprise.

This video continues at https://youtu.be/Yh1QUYn2f3I and delves into so-called Untouchable Numbers.

Ben Sparks: https://www.bensparks.co.uk

More Ben Sparks on Numberphile: http://bit.ly/Sparks_Playlist

Perfect Numbers on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJILwhaYs0Cz76-XK4cu3WC

Amicable Numbers: https://youtu.be/fUSZBVYZdKY