device memory its just full of system memory My internal memory is full of system memory, I have 4 GB and all that is system memory. I cannot instal any apps, cannot take a picture. My phone is rooted. I also try to reset factory setting, but nothing happens.

what will i do?
I think your whole 4GB memory is in System Partition. 
If your bootloader is unlocked Download TWRP Recovery and install it. Then reboot into recovery and repartition your System. 500MB-1GB is enough for System Partition.