Do you win anything with one number on Mega Millions? If you match just the Mega Ball (and don't match any of the five regular numbers), you win aR$2 prize and break even on theR$2 cost of your Mega Millions ticket. However, If you match one white ball but not the Mega Ball, there is no prize.
Technically you can win Powerball with just one number. If you hit on the Powerball number, you get a prize ofR$4. If you get one ball correct, you have to also hit the Powerball to winR$4. If you hit two balls and the Powerball, you winR$7.