Choose the most powerful GPU you can find and see what it's rate is. Then you can calculate to see how long it will take to scan the whole range 
It's not necessary to scan the whole range as it's not necessary to buy all lottery tickets to win, if you are lucky (random or picking small random ranges) you can win the challenge.When i was 18 y.o. with a single dollar I matched 12 results in a row of football matches and I won $5000, it could have been 13 results (the maximum) but one result changed at the last minute (I would have won $250000). And I wasn't a football expert, I wrote them at random.
