How do you recognise landline phone number versus mobile phone number/Krakow?

Hello,
Does anyone know how to recognise by the number if the line is from a landline or mobile phone in Krakow ?

For instance 012 then 500... , or 012 then 648 ...
There is a big price difference so i would prefer to chat on landline phones only!

Thanks a lot for your info, I have been trying to find out but in vain.

If it is 012 xxx xxxx it is a landline. Mobiles are 05(0/1)x xxxxxx and 06(0/9)x xxxxxx and 07(7/9)x xxxxxx.

Thanks Harry.