The large number "RSA-129" posed a challenge experts said would take 40 quadrillion years to solve - but took 17. Featuring Ron Rivest, co-inventor of RSA... More links below... Our original RSA video (how it all works): https://www.youtube.com/watch?v=M7kEpw1tn50 More from Ron from this interview (quantum computing): https://www.youtube.com/watch?v=tX7e7CgWrvM More Ron Rivest on Numberphile: http://bit.ly/RonRivest Ron Rivest's own website: https://people.csail.mit.edu/rivest/ Public Key Cryptography on our sister channel, Computerphile: https://www.youtube.com/watch?v=GSIDS_lvRv4 RSA-129: 114381625757888867669235779976146612010218296721242362562561842935706935245733897830597123563958705058989075147599290026879543541 Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://bit.ly/MSRINumberphile We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science. NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile Numberphile tweets: https://twitter.com/numberphile Subscribe: http://bit.ly/Numberphile_Sub Videos by Brady Haran Patreon: http://www.patreon.com/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9