64% is not too bad for the first try. As amateur said, you should get at least 80% to get into top schools. I know some schools they say they even don't care to GRE general , they prefer GRE maths
By the way, I do have a question
: is it true that the November's score will be sent to designated universities on December 20 OR December 20 is just the day we are informed score ?
I'm worry it may be too late for schools whose deadline is December 1