Maths - Tests of Divisibility

A number is divisible by  2 : if its unit digit is 0,2,4,6, or 8

                                    by  3 : if the sum of its digits is divisible by 3

                                    by  4 : if the number formed by its last two digits
                                              is divisible by 4

                                    by  5 : if its unit digit is either 0 or 5

                                    by  6 : if it is divisble by 2 and 3

                                    by  8 : if the number formed by its last three digits
                                              is divisible by 8

                                    by  9 : if the sum of its digits is divisible by 9

                                   by 10 : if its unit digit is  0

                                   by 11 : if the differnce between the sum of its
                                               alternate digits is 0 or mutiple of 11.

                                   by 12 : if the number is divisible by 3 and 4

                                   by 25 : if the number formed by its last two digits
                                               is divisible by 25