# FAQ

**Is x prime?**

Please try our number cruncher. If your question is more complex then try using the contact form. I can't promise a quick response though.

**I've taken the time to send you an email. Why haven't you responded?!**

I apologise, I run this site in what little spare time I have. You will get a response.

**I've found a bug/mistake on bigprimes.net!**

Please send me an email using the contact form.

**What is the first set of 100 numbers (e.g. 100-199, 1300-1399, 312300-312399) that does not contain a prime number?**

The first occurrence is between the prime numbers 1671781 and 1671907 on this page (near bottom of 3rd column).

**What is the smallest prime number that contains all digits 0 to 9 in sequence?**

100123456789

**What percentage of prime numbers end in 1,3,7 and 9?**

25% of prime numbers end in a 1

25% of prime numbers end in a 3

25% of prime numbers end in a 7

25% of prime numbers end in a 9