Can you get pregnant by rubbing semen on the vagina? what are the odds of getting pregnant this way?

No : The vaginal vault is a natural hostile environment for sperm due to the ph. A male's normal sperm count is 20-40 million per millimeter, and a low sperm count is less than 15 million per millimeter. The dilution of semen decreases this count and the ph of skin kills the sperm. Lastly, there is still a relatively great distance to travel to reach the ovum.