Ask HN: Why does Google fail to judge whether X is prime

6 points

6 years ago

If you type "is 1000000007 prime" into google, you'll find that google suggests that 1000000007 is not a prime. See https://i.imgur.com/ZWyoxLx.png

However, 1000000007 is a well-known prime used in many programming competitions or online judges.

The same thing will happen if you type "is 15485863 prime" into google. (which is the 1000000th prime) See https://i.imgur.com/vrCKqL7.png

Perhaps, starting with 1299709 (the 100000th prime), the answers might be all wrong.

It seems that determining whether an input number is prime should not go wrong easily. So, why does google fail to do that?

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