# Prime Factors of 391

Prime Factors of 391 are 17 and 23

#### How to find prime factors of a number

 1.   Prime Factorization of 391 by Division Method 2.   Prime Factorization of 391 by Factor Tree Method 3.   Definition of Prime Factors 4.   Frequently Asked Questions

#### Steps to find Prime Factors of 391 by Division Method

To find the primefactors of 391 using the division method, follow these steps:

• Step 1. Start dividing 391 by the smallest prime number, i.e., 2, 3, 5, and so on. Find the smallest prime factor of the number.
• Step 2. After finding the smallest prime factor of the number 391, which is 17. Divide 391 by 17 to obtain the quotient (23).
391 ÷ 17 = 23
• Step 3. Repeat step 1 with the obtained quotient (23).
23 ÷ 23 = 1

So, the prime factorization of 391 is, 391 = 17 x 23.

#### Steps to find Prime Factors of 391 by Factor Tree Method

We can follow the same procedure using the factor tree of 391 as shown below:

So, the prime factorization of 391 is, 391 = 17 x 23.

#### Introduction to Prime Factors?

In mathematics, prime numbers are defined as all those natural numbers greater than 1 that has only two divisors one being number 1 and the other being the number itself. When we express any number as the products of these prime numbers than these prime numbers become prime factors of that number. Eg- Prime Factors of 391 are 17 x 23.

#### Properties of Prime Factors

• For any given number there is one and only one set of unique prime factors.
• 2 is the only even prime number. So, any given number can have only one even prime factor and that is 2.
• Two prime factors of a given number are always coprime to each other.
• 1 is neither a prime number nor a composite number and also 1 is the factor of every given number. So, 1 is the factor of 391 but not a prime factor of 391.

• Which is the smallest prime factor of 391?

Smallest prime factor of 391 is 17.

• What are the factors of 391?

Factors of 391 are 1 , 17 , 23 , 391.

• What is prime factorization of 391 in exponential form?

Prime factorization of 391 in exponential form is 17 x 23.

• Is 391 a prime number or a composite number?

391 is a composite number.

• Is 391 a prime number?

false, 391 is not a prime number.

• What is the sum of all prime factors of 391?

Prime factors of 391 are 17 x 23. Therefore, their sum is 40.

• What is the product of all prime factors of 391?

Prime factors of 391 are 17 x 23. Therefore, their product is 391.

• What numbers are the prime factors of 391?

Prime factors of 391 are 17 , 23.

• What is the sum of all odd prime factors of 391?

Prime factors of 391 are 17 , 23, out of which 17 , 23 are odd numbers. So, the sum of odd prime factors of 391 is 17 + 23 = 40.