Is there any way to stop Ghenghis Khan?

I have been playing CK3 for around 1 month and in my current play through (im five generations in) I have just united Cumania and finally quelled all my vassals. As I was taking over Georgia with my 25000 troops Ghenghis Khan declared war on me with 70000 troops. I have allies in Europe but all of them are at war and wont reach me in time is there anything I can do to survive I would just submit to him but I am an empire as well.