Test 13 for Divisibility by 3

Given Number: 13
Test a Number for Divisibility by Three (3):
• A Number is divisible by 3 if the Sum of the Digits in the Number is divisible by 3
Sum of the Digits in 13: 1+3 = 4
4 is not divisible by 3
Therefore, 13 is NOT divisible by 3
Note: Since 13 is not divisible by 3, it follows that 13 is also not divisible by any multiple of 3 (6, 9, 12, …)

The solution above and all other related solutions were provided by the Test for Divisibility by 3 Application.