If sum of all digits in the number is divisible by 3 or 9, then
the number is divisible by 3 or 9.
(1.) 3,123,456
3+1+2+3+4+5+6 = 24
You can divide 24 by 3, but can't divide by 9, therefore 3,123,456 is divisible by 3, but not by 9.
If last digit of the number is even, then number is divisible by 2.
(2.) 3,123,456
6 is even number, therefore the given number is divisible by 2.
6 / 2 = 3 ------> the given number is not divisible by 4, because 3 is odd number.
From (1.) and (2.) -----> the given number is divisible by 6
If last digit in the number 0 or 5, then number is divisible by 5.
Comments