Magic Number

Jack loves to play with numbers. One day, while he was playing with numbers he found something interesting. He saw some numbers were indivisible without 1 and the number itself. He named those number as magic number.

This is a companion discussion topic for the original entry at

*** Here, 15, 56, 32 is not a Magic number :crazy_face: , but 9, 25, 49… they are Magic number :nerd_face: