There are just four natural numbers less than $$ 100 $$ , which have exactly three factors. One of them is $$ 25 $$ , what are the other three ? What can be said about these numbers ?
Four natural numbers less than $$ 100 $$ which have three factors :
One of them is $$ 25 = 1 , 5 , 25 $$
Second is $$ 49 = 1 , 7 , 49 $$
Third is $$ 9 = 1 , 3 , 9 $$
Fourth is $$ 4 = 1 , 2 , 4 $$