Factors of 645

The numbers that divide 645 evenly are known as factors of 645. A factor of 645 is a number that divides the number without remainder. The factors of 645 are 1, 3, 5, 15, 43, 129, 215, and 645.

Negative factors of 645: -1, -3, -5, -15, -43, -129, -215, and -645.

Prime factors of 645: 3, 5, and 43.

Prime factorization of 645: 3 × 5 × 43.

The sum of factors of 645: 1 + 3 + 5 + 15 + 43 + 129 + 215 + 645 = 1056

Factors can be found using different methods. Mentioned below are some commonly used methods:

1. Finding factors using multiplication
2. Finding factors using division method
3. Prime factors and Prime factorization

To find factors using multiplication, we need to identify the pairs of numbers that are multiplied to give 645. Identifying the numbers which are multiplied to get the number 645 is the multiplication method.

Step 1: Multiply 645 by 1, 645 × 1 = 645.

Step 2: Check for other numbers that give 645 after multiplying

3 × 215 = 645

5 × 129 = 645

15 × 43 = 645

Therefore, the positive factor pairs of 645 are: (1, 645), (3, 215), (5, 129), (15, 43). All these factor pairs result in 645. For every positive factor, there is a negative factor.

Dividing the given numbers with the whole numbers until the remainder becomes zero and listing out the numbers that result as whole numbers as factors. Factors can be calculated by following the simple division method:

Step 1: Divide 645 by 1, 645 ÷ 1 = 645.

Step 2: Continue dividing 645 by the numbers until the remainder becomes 0.

645 ÷ 1 = 645

645 ÷ 3 = 215

645 ÷ 5 = 129

645 ÷ 15 = 43

Therefore, the factors of 645 are: 1, 3, 5, 15, 43, 129, 215, 645.

The factors can be found by dividing it with a prime number. We can find the prime factors using the following methods:

• Using prime factorization
• Using factor tree

Using Prime Factorization: In this process, prime factors of 645 divide the number to break it down in the multiplication form of prime factors till the remainder becomes 1.

645 ÷ 3 = 215

215 ÷ 5 = 43

43 ÷ 43 = 1

The prime factors of 645 are 3, 5, and 43. The prime factorization of 645 is: 3 × 5 × 43.

The factor tree is the graphical representation of breaking down any number into prime factors. The following step shows:

Step 1: Firstly, 645 is divided by 3 to get 215.

Step 2: Now divide 215 by 5 to get 43.

Step 3: Then divide 43 by 43 to get 1. Here, 43 is the smallest prime number that cannot be divided anymore. So, the prime factorization of 645 is: 3 × 5 × 43.

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 645: (1, 645), (3, 215), (5, 129), and (15, 43).
• Negative factor pairs of 645: (-1, -645), (-3, -215), (-5, -129), and (-15, -43).

• Factors: The numbers that divide the given number without leaving a remainder are called factors. For example, the factors of 645 are 1, 3, 5, 15, 43, 129, 215, and 645.

• Prime factors: The factors which are prime numbers. For example, 3, 5, and 43 are the prime factors of 645.

• Factor pairs: Two numbers in a pair that are multiplied to give the original number are called factor pairs. For example, the factor pairs of 645 are (1, 645), (3, 215), etc.

• Negative factors: Factors that are negative and divide the number without remainder. For example, -1, -3, -5, etc., are negative factors of 645.

• Prime factorization: The expression of a number as a product of its prime factors. For example, the prime factorization of 645 is 3 × 5 × 43.