How many prime numbers has been discovered to this day and what is at the moment highest prime number?
Many. Hope that helps.Originally Posted by OReilly
There is a class of primes called "Mersenne Primes" they have form $\displaystyle 2^n-1$. One interesting fact is that if this number is prime then $\displaystyle n$ must it self be prime! If I remember properly-(I might be wrong)that,
$\displaystyle 2^{65537}-1$ is prime,
I only remember that because
$\displaystyle 65537=2^{2^4}+1$ a Fermat prime.
I think it might be among the highest.
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