There are balls in the lottery numbered from 1 to 1919, so there are total 1919 balls. In order to win 5 balls must be selected, but it is also very important to note that also the order of the selected balls must be correct in order to win. Because the order plays also a role, we are dealing with permutations, and not combinations. Permutation is an ordered combination:
P=n!/(n-k)!, where we choose k objects from n. In our case, n=1919 and k=5
P=1919!/(1919-5)!=1919!/1914!=1919*1918*1917*1916*1915*1914!/1914!=
1919*1918*1917*1916*1915= 2.58*10^16
There are 2.58*10^16 possible outcomes.