# Divisibility by 13

Any number is said to be divisible by 13, when you add “four times of ones digit” with the remaining number, and the result is divisible by 13.

For example: Is 325 divisible by 13?

Step 1: Ones digit of 325 is 5, so the result = 32 + (4 x 5) = 32 + 20 = 52

Step 2: Check if result, 52 is divisible by 13.

Here, 52 ÷ 13 = 4, i.e. 52 is perfectly divisible by 13.

Hence, number 325 is divisible by 13.

Note: If the result obtained from above operation is a big number, then this technique can be continued till you get a smaller (may be upto 2 digit figures) numbers.

For example: Is 222222 divisible by 13?

Step 1: Figure 1: 22222 + (4 x 2) = 22230

Step 2: Figure 2: 2223 + (4 x 0) = 2223

Step 3: Figure 3: 222 + (4 x 3) = 222 + 12 = 234

Step 4: Figure 4: 23 + (4 x 4) = 39

As 39 is divisible by 13, so our number 222222 is also divisible by 13.

Practice Questions:

Check whether below numbers are divisible by 13?

a. 4566             b. 1246            c. 1040        d. 5642              e. 22124

f.  244               g. 3636             h. 975         i. 2860                j. 5551