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Can I just say how surprised I am the many people have a favourite prime number generator.

I can’t say I have a favourite but I do enjoy multiplying two random prime numbers with each other and using the random result when I need a random number with added random.

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That doesn't seem like a good way to generate "random" numbers, since it will only produce numbers with exactly two prime factors.

Correct. It will almost never produce an even number, so there's already one bit of entropy lost. It will also never produce lots of other numbers.

Thanks all, I hadn’t considered that but we do only use it for silly things and nothing work related but it’s worth a consideration.

A way to add even more random is to generate a list of N random primes, then shuffling it M times before multiplying the elements. N and M are of course random positive integers.

To add maximum random, sometimes I like to return a string with a random Gertrude Stein quote, segfault, or make the PC speaker beep instead of returning a number. So random!

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