I can't bend my big toe up,but there's no pain,and it also feels numb?

Be seen : I would be seen. The L5 nerve root is the nerve that supplies the EHL which is the muscle that raises the big toe. Your weakness and numbness suggest severe compression of that nerve being one of the most likely causes. Don't hesitate to be seen for treatment alternatives.

It's abnormal: You should be able to bend the big toe (called the 'hallux') downward. It if far more important to be able to bend it upward though. It may be an early stage of hallux rigidis. This is when the big toe joint gets stiff. Often there is a small nerve that can get irritated, leading to numbness. See a podiatrist for exact advice in your specific case.

Great toe Caper.: Most importantly, is it that you cannot bend it by your normal brain control, or will the toe not bend even if you do it manually. The difference is whether or not there is a bone blockage or arthritic stiffening of the joint or the nerve that controls the muscle to the toe has been compromised. The treatment protocol and prognosis for each circumstance varies.