Is 73 a Prime Number?

IS 73 A PRIME NUMBER?

Yes, 73 is a prime number. What is a prime number? Whole numbers are classified as prime or composite. When a number cannot be written as a product of more than two factors which are the number itself and 1, then it is a prime number. If it has more than 2 factors then it is a non-prime (composite) number. 

For example: 11 has only two factors which are 1 and 11. It is a prime number.

29 is a prime number because it also has two factors which are 1 and 29.

55 having more than two factors is a composite (non-prime) number. The factors of 55 are 1, 5, 11, 55.

WHAT ARE THE FACTORS OF 73?

Since 73 cannot be written as a product of any two numbers other than 1 and 73. 

73 = 1 x 73

Thus, making it a prime number?

73 IS A PRIME NUMBER – EXPLANATION

For a number to be a prime number, it must not be a multiple of any prime numbers below 10. The prime numbers which are less than 10 are 2, 3, 5 and 7. 

Since 73 does not have 0, 2, 4, 6 or 8 at its end so it is not a multiple of 2. The sum of the digits 7 + 3 = 10 which is not a multiple of 3 so it is not divisible by 3. The number doesn’t end in 0 or 5 so it is not a multiple of 5 and 73 is not divisible by 7 either.

The square root of 73 is 8.544. Therefore, it is not a perfect square either.

It has only two factors which are 1 and 73.

Thus 73 can be represented as a product of 1 and 73.