Converse and Contrapositive

Hello everyone!

i am strungling here doing my excersise actually, lets see now, i have this expression : A positive integer is a prime number only if it doesnt have divisor past 1 and itself.

Converse is : If an integer doesnt have divisor past 1 and itself then its a positive integer prime number.

Cotrapositive is : A positive integer is not a prime number only if it does have divisor past 1 and itself .

Am i right? any suggestions?

By the way i might have translated bad the definition of prime numbers from my native language into english, so please excuse me.

thanks again for your help.