Easily test if any number is evenly divisible by 7
Is 9745764 divisible by 7?
Step 1
Multiply the ones digit by 1
4 x 1 = 4
Step 2
Multiply the tens digit by 3
6 x 3 = 18
Step 3
Multiply the hundreds digit by 2
7 x 2 = 14
Step 4
Multiply the thousands digit by -1
-1 x 5 = -5
Step 5
Multiply the ten thousands digit by -3
-3 x 4 = -12
Step 6
Multiply the hundred thousands digit by -2
-2 x 7 = -14
Step 7
Keep multiplying each additional digit by 1,3,2,-1,-3,-2 and so forth until all digits are used.
1 x 9 = 9
Step 8
Add the results of all steps.
4 + 18 + 14 - 5 - 12 - 14 + 9 = 14
Step 9
Divide step 8 by 7
14 / 7 = 2
Step 10
The original number is evenly divisible by 7 if the result of step 9 is a whole number.
Yes