# Divisibility and factors

A number is considered divisible by another number (divisibility) when the result of the division is an integer and there is no remainder. The number which divides that number is called a factor of that number or its divisor. Division is an operation that is the opposite of multiplying and the property that a number can be divided by another number is called divisibility.
For example: If you divide the number 16 with the number 2, you will get the number 8 as a result and no remainder. That means that the number 16 is divisible by the number 2 and that 2 is a factor of 16. But if you divide the number 16 with the number 3, you will get the number 5 as a result with 1 as the remainder. This means that 16 is not divisible by 3 and 3 is not a factor of 16.

The basic rules that can help you determine whether a number can be divided by another number (and which one) are ilustrated in the picture below. These rules are particularly useful in prime factorization or finding the least common multiple or the greatest common factor. ## Divisibility exams for teachers

 Exam Name File Size Downloads Upload date Positive integers Divisibility of positive integers – very easy 107.1 kB 4720 September 3, 2019 Divisibility of positive integers – easy 157.4 kB 3384 September 3, 2019 Divisibility of positive integers – medium 164.8 kB 4037 September 3, 2019 Divisibility of positive integers – hard 179.1 kB 3253 September 3, 2019 Positive decimals Divisibility of positive decimals – very easy 559.2 kB 1656 September 3, 2019 Divisibility of positive decimals – easy 572.4 kB 1595 September 3, 2019 Divisibility of positive decimals – medium 575.7 kB 1542 September 3, 2019 Divisibility of positive decimals – hard 561.3 kB 1550 September 3, 2019 Positive fractions Divisibility of positive fractions – very easy 119 kB 1591 September 3, 2019 Divisibility of positive fractions – easy 564.6 kB 1452 September 3, 2019 Divisibility of positive fractions – medium 572.1 kB 1589 September 3, 2019 Divisibility of positive fractions – hard 576.9 kB 1356 September 3, 2019 Positive mixed numbers Divisibility of positive mixed numbers – easy 568.8 kB 1464 September 3, 2019 Divisibility of positive mixed numbers – medium 583.9 kB 1323 September 3, 2019 Divisibility of positive mixed numbers – hard 612.3 kB 1285 September 3, 2019 Positive improper fractions Divisibility of positive improper fractions – very easy 170.5 kB 1325 September 3, 2019 Divisibility of positive improper fractions – easy 564.5 kB 1245 September 3, 2019 Divisibility of positive improper fractions – medium 564.4 kB 1199 September 3, 2019 Divisibility of positive improper fractions – hard 574.6 kB 1323 September 3, 2019 Divisibility of positive improper fractions – very hard 574.1 kB 1209 September 3, 2019 Non positive integers Divisibility of integers – very easy 82.3 kB 1503 September 3, 2019 Divisibility of integers – easy 154.6 kB 1514 September 3, 2019 Divisibility of integers – medium 163.2 kB 1761 September 3, 2019 Divisibility of integers – hard 173.4 kB 1854 September 3, 2019 Non positive decimals Divisibility of decimals – very easy 567.8 kB 1352 September 3, 2019 Divisibility of decimals – easy 559.9 kB 1489 September 3, 2019 Divisibility of decimals – medium 557 kB 1292 September 3, 2019 Divisibility of decimals – hard 559.6 kB 1590 September 3, 2019 Non positive fractions Divisibility of fractions – very easy 552.2 kB 1321 September 3, 2019 Divisibility of fractions – easy 569.2 kB 1391 September 3, 2019 Divisibility of fractions – medium 571.5 kB 1289 September 3, 2019 Divisibility of fractions – hard 595.4 kB 1372 September 3, 2019 Non positive mixed numbers Divisibility of mixed numbers – easy 559.7 kB 1359 September 3, 2019 Divisibility of mixed numbers – medium 588.7 kB 1332 September 3, 2019 Divisibility of mixed numbers – hard 585.2 kB 1248 September 3, 2019 Non positive improper fractions Divisibility of improper fractions – easy 175 kB 1562 September 3, 2019 Divisibility of improper fractions – medium 183.4 kB 1439 September 3, 2019 Divisibility of improper fractions – hard 212.8 kB 1613 September 3, 2019

There are tricks and shortcuts in the process of determination whether a number is divisible by another number.
Every number, including prime numbers, is divisible by the number 1 and itself.
All even numbers (those ending in 0, 2, 4, 6 or 8 ) are divisible by 2.
If you calculate the sum of all the digits in a number and that sum is divisible by 3, then the number is divisible by 3 as well.
A number is divisible by 4 if the last two digits in that number are divisible by 4.
Every number ending in 0 or 5 is divisible by the number 5.
A number is divisible by 6 if it is also divisible by 2 and 3.
If the last three digits in a number are divisible by 8, then that whole number is divisible by 8.
The same rule applies for checking if a number is divisible by the number 9 as it does for number 3. If the sum of all digits in the number is divisible by 9, then the entire number is divisible by 9.
Every number ending in 0 is divisible by the number 10.

## Factoring exams for teachers

 Exam Name File Size Downloads Upload date Factoring all positive factors 119.1 kB 2808 September 3, 2019 Factoring numbers without exponents 125.7 kB 1878 September 3, 2019 Factoring with exponents 129.8 kB 2437 September 3, 2019

## Divisibility and factoring worksheets for students

 Worksheet Name File Size Downloads Upload date Positive Divisibility of positive integers 137.7 kB 2256 September 3, 2019 Divisibility of positive decimals 192.9 kB 1484 September 3, 2019 Divisibility of positive fractions 252.6 kB 1296 September 3, 2019 Divisibility of positive mixed numbers 227 kB 1228 September 3, 2019 Divisibility of positive improper fractions 248.8 kB 1277 September 3, 2019 Non positive Divisibility of integers 143.7 kB 1541 September 3, 2019 Divisibility of decimals 222.3 kB 1355 September 3, 2019 Divisibility of fractions 260.9 kB 1372 September 3, 2019 Divisibility of mixed numbers 276.9 kB 1245 September 3, 2019 Divisibility of improper fractions 234.4 kB 1288 September 3, 2019 Factoring numbers Factoring 198.2 kB 2619 September 3, 2019