This video is part of the #MegaFavNumbers series where a tonne of math youtubers like https://www.youtube.com/channel/UCoxcjq-8xIDTYp3uz647V5A https://www.youtube.com/channel/UCSju5G2aFaWMqn-_0YBtq5A and https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw share their favourite MEGA numbers, i.e. numbers over a million. Check out the full playlist here:    • MegaFavNumbers   In my video, I'm talking about Mersenne primes. These are a special type of prime of the form 2^p-1. If p is a prime, sometimes 2^p-1 is prime, and sometimes composite. However, they are great candidates to be prime, and in particular come with a test called the Lucas-Lehmer primality test which provides a more computationally efficient test of whether a Mersenne number is prime than generic numbers of similar sizes. So far the largest prime number we have found - also the largest Mersenne prime - is 2^82589933-1 which is an enormous number! You can learn more about the search for Mersenne primes and even help find new ones at the Great Internet Mersenne Prime Search https://www.mersenne.org/. COURSE PLAYLISTS: ►CALCULUS I:    • Calculus I (Limits, Derivative, Integ...   ► CALCULUS II:    • Calculus II (Integration Methods, Ser...   ►MULTIVARIABLE CALCULUS (Calc III):    • Calculus III: Multivariable Calculus ...   ►DIFFERENTIAL EQUATIONS (Calc IV): https://www.youtube.com/watch?v=xeeM3TT4Zgg ►DISCRETE MATH:    • Discrete Math (Full Course: Sets, Log...   ►LINEAR ALGEBRA:    • Linear Algebra (Full Course)   OTHER PLAYLISTS: ► Learning Math Series https://www.youtube.com/watch?v=LPH2lqis3D0 ►Cool Math Series:    • Cool Math Series   BECOME A MEMBER: ►Join: null MATH BOOKS & MERCH I LOVE: ► My Amazon Affiliate Shop: https://www.amazon.com/shop/treforbazett SOCIALS: ►Twitter (math based): http://twitter.com/treforbazett ►Instagram (photography based): http://instagram.com/treforphotography