Do you know that this famous Hot Spring National Park in the United States of America has a total of **47** hot springs?

Another fact that we're going to study today is that 47 is a prime number since it has only two factors: 1 and the number itself.

This chapter will explore other topics like prime numbers, is 97 a prime number, is 49 a prime number, is 57 a prime number, and is 91 a prime number in the concept of is 47 a prime number.

Check out the interactive questions to know more about the lesson and try your hand at solving a few interesting practice questions at the end of the page.

**Lesson Plan **

**What Is a Prime Number?**

Any whole number which is greater than 1, and has only 2 factors, 1 and the number itself, is called a prime number.

The number clearly has only two factors, 1 and the number 47

Thus, observing the factors of 47, we conclude that it is a prime number.

**Examples:**

Let us see a few more examples.

- Factors of number 97 = 1, 97. So, is 97 a prime number? Yes, because it has only 2 factors.
- Factors of number 57 = 1, 57. So, is 57 a prime number? Yes, because it has only 2 factors.
- Factors of number 91 = 1, 7, 13, 91. So, is 91 a prime number? No, because it has 4 factors.
- Factors of number 49 = 1, 7, 49. So, is 49 a prime number? No, because it has 3 factors.

**Is 47 a Prime Number?**

To check if a number is prime or not, we find out all the factors of the number.

This can be done using different methods:

- Divison of the number by all the prime numbers starting from 1
- By prime factorization

After following one of the above steps, we find all the possible factors of the number and thus conclude if the number is prime or not.

**Let us check this for 47:**

Observe the figure which shows the prime factorization of 47:

The prime factors of 47 = 1 and 47

Thus, even by repeated multiplication of its prime factors, 47 has only two factors in all = 1 and 47

Hence, 47 is a prime number.

- 47 has only 2 factors, 1 and 47 itself, so it is a prime number.
- We don't take the negative factors of a number into consideration to check whether it is prime or not.

**Is 47 a Composite Number?**

A composite number has more than two factors.

Since 47 has exactly two factors: 1 and 47, it is not a composite number.

**Solved Examples**

Example 1 |

Loren is preparing a list of all prime numbers. Can you help her find the number of prime numbers that are less than 47?

**Solution**

All the prime numbers less than 47 = 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43

The number of prime numbers less than 47 is 14

\( \therefore \) The number of prime numbers less than 47 are 14 |

Example 2 |

Joel needs to prove that 1 added to or subtracted from 47 makes it a composite number. How will he prove it?

**Solution**

On adding 1 to 47, Joel gets 48

Factors of 48 = 1, 2, 3, 4, 6, 8, 12, 16, 24, and 48

Clearly, 48 has more than 2 factors. Thus, it is not a prime number.

On subtracting 1 from 47, he gets 46

Factors of number 46 = 1, 2, 23, and 46

It has factors other than 1 and 46, which makes it a composite number.

Hence, 1 added to or subtracted from 47 makes it a composite number.

\( \therefore \)1 added to or subtracted from 47 makes it a composite number. |

**Interactive Questions**

**Here are a few activities for you to practice. **

**Select/Type your answer and click the "Check Answer" button to see the result.**

- Leslie needs to find those prime numbers between 1 to 100 whose sum also gives a prime number. Can you help him?
- How will Jamie check if 51 is a prime number or not?

**Let's Summarize**

The mini-lesson targeted the fascinating concept of the "Is 47 a prime number". The math journey around the "Is 47 a prime number" starts with what a student already knows, and goes on to creatively crafting a fresh concept in the young minds. Done in a way that not only it is relatable and easy to grasp, but also will stay with them forever. Here lies the magic with Cuemath.

**About Cuemath**

At Cuemath, our team of math experts is dedicated to making learning fun for our favorite readers, the students!

Through an interactive and engaging learning-teaching-learning approach, the teachers explore all angles of a topic.

Be it worksheets, online classes, doubt sessions, or any other form of relation, it’s the logical thinking and smart learning approach that we, at Cuemath, believe in.

**Frequently Asked Questions (FAQs)**

## 1. What can 47 be divided by?

47 is a prime number, which means it has only two factors 1 and 47. Thus, it can only be divided by 1 and 47

## 2. Is 47 a prime number? Yes or no?

Yes, 47 is a prime number because it has only two factors, 1 and the number itself.

Factors of 47 = 1 and 47

## 3. Is 47 a perfect square?

The square root of 47 = \( \sqrt{47}\) = 6.85565, which is not a whole number.

Thus, 47 is not a perfect square.