BUT...51 isn't a prime number. It has more than 2 factors, i.e. 1, 3, 17, 51.
By the way, a trick I learned way, way, way back in pri school is that if you add all the digits of number up and the result is perfectly divisible by 3, then that number is also divisible by 3.
2 comments:
BUT...51 isn't a prime number. It has more than 2 factors, i.e. 1, 3, 17, 51.
By the way, a trick I learned way, way, way back in pri school is that if you add all the digits of number up and the result is perfectly divisible by 3, then that number is also divisible by 3.
Try it with 51! :)
*faints* yes, you re right :( 51 is not a prime number. aiyoh :(
Post a Comment