Easily test if any number is evenly divisible by 3
Example
Is 947244 divisible by 3?
Yes
Step 1
Add together each digit in the number.
9+4+7+2+4+4 = 30
Step 2
Divide step 1 by 3
30 / 3 = 10
Step 3
The original number is evenly divisible by 3 if the result of step 2 is a whole number.
Yes