Last updated on June 4th, 2025
Factors are the numbers that divide any given number evenly without remainder. In daily life, we use factors for tasks like sharing items equally, arranging things, etc. In this topic, we will learn about the factors of -40, how they are used in real life, and tips to learn them quickly.
The numbers that divide -40 evenly are known as factors of -40.
A factor of -40 is a number that divides the number without remainder.
The positive factors of -40 are 1, 2, 4, 5, 8, 10, 20, and 40.
Negative factors of -40: -1, -2, -4, -5, -8, -10, -20, and -40.
Prime factors of 40 (ignoring the sign): 2 and 5.
Prime factorization of 40: 23 × 5.
The sum of the positive factors of 40: 1 + 2 + 4 + 5 + 8 + 10 + 20 + 40 = 90
Factors can be found using different methods. Mentioned below are some commonly used methods:
To find factors using multiplication, we need to identify the pairs of numbers that are multiplied to give -40. Identifying the numbers which are multiplied to get the number -40 is the multiplication method.
Step 1: Multiply -40 by 1, -40 × 1 = -40.
Step 2: Check for other numbers that give -40 after multiplying -2 × 20 = -40
-4 × 10 = -40
-5 × 8 = -40
Therefore, the positive factor pairs of -40 are: (1, -40), (2, -20), (4, -10), (5, -8).
For every positive factor, there is a negative factor.
Dividing the given numbers with whole numbers until the remainder becomes zero and listing out the numbers which result as whole numbers as factors. Factors can be calculated by following a simple division method:
Step 1: Divide -40 by 1,
-40 ÷ 1 = -40.
Step 2: Continue dividing -40 by the numbers until the remainder becomes 0.
-40 ÷ 1 = -40
-40 ÷ 2 = -20
-40 ÷ 4 = -10
-40 ÷ 5 = -8
Therefore, the factors of -40 are: 1, 2, 4, 5, 8, 10, 20, 40.
The factors can be found by dividing it with prime numbers. We can find the prime factors using the following methods:
Using Prime Factorization: In this process, prime factors of 40 divide the number to break it down in the multiplication form of prime factors till the remainder becomes 1.
40 ÷ 2 = 20
20 ÷ 2 = 10
10 ÷ 2 = 5
5 ÷ 5 = 1
The prime factors of 40 are 2 and 5.
The prime factorization of 40 is: 23 × 5.
The factor tree is the graphical representation of breaking down any number into prime factors. The following steps show:
Step 1: Firstly, 40 is divided by 2 to get 20.
Step 2: Now divide 20 by 2 to get 10.
Step 3: Then divide 10 by 2 to get 5. Here, 5 is the smallest prime number, that cannot be divided anymore.
So, the prime factorization of 40 is: 23 × 5.
Factor Pairs: Two numbers that are multiplied to give a specific number are called factor pairs. Both positive and negative factors constitute factor pairs.
Positive factor pairs of -40: (1, -40), (2, -20), (4, -10), (5, -8).
Negative factor pairs of -40: (-1, 40), (-2, 20), (-4, 10), (-5, 8).
Mistakes are common while finding factors. We can identify and correct those mistakes using the following common mistakes and the ways to avoid them.
There are 4 teams and 40 points to distribute equally among them. How will they divide it equally?
They will get 10 points each.
To divide the points equally, we need to divide the total points by the number of teams.
40/4 = 10
A fence is 10 meters long, and the total area to be fenced is 40 square meters. Find the width of the fenced area?
4 meters.
To find the width of the fenced area, we use the formula, Area = length × width
40 = 10 × width
To find the value of width, we need to shift 10 to the left side.
40/10 = width
Width = 4.
There are 5 boxes and 40 apples. How many apples will be in each box?
Each box will have 8 apples.
To find the apples in each box, divide the total apples by the boxes.
40/5 = 8
In a class, there are 40 students, and they are divided into 8 groups. How many students are there in each group?
There are 5 students in each group.
Dividing the students with the total groups, we will get the number of students in each group.
40/8 = 5
40 books need to be placed on 10 shelves. How many books will go on each shelf?
Each of the shelves has 4 books.
Divide the total books by the number of shelves.
40/10 = 4
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.