I'm pretty sure about 17x reds, 18xreds but 22x is to much for 2x.
Sounds too much but in fact 22x is still possible on x2, afaik there was a player get more than 30x on x2. My worst was 25x long time ago, so dont ever think that it is impossible. Every single roll is independent, when you are so unlucky then you will get something that you think is impossible.