Er, no car has 4000Nm of torque, not even top fuel dragsters.
You're reading the the RPM point at which torque peaks.
Torque is measured in Nm or lb/ft, not RPM. RPM measures engine speed.
4000 refers to 4000rpm, which means you get maximum torque at 4000rpm.
It's alright. cars are technical. Not everyone can understand them.
Don't feel bad.