A given number for which sum of all its factors is equal to it's twice, the number is known as A Perfect Number
Read the following examples to understand more about Perfect Numbers
Examples 1 = Is given number 6 a prime number ?
Answer = Find the factors of given number 6
Factors of 6 = 1, 2, 3, 6.
Now, add all the above factors.
Sum = 1 + 2 + 3 + 6 = 12
Now, you can calculate that twice of given number 6 = 12
Since the sum of all the factors of 6 is equal to its twice
So, we can say that 6 is a perfect number.