A perfect number is a positive integer that is equal to the sum of its proper positive divisors, that is, the sum of its positive divisors excluding the number itself.
Or we can say that a perfect number is a number that is half the sum of all of its positive divisors (including itself).
First perfect number is 6. Lets check out how it is a perfect number.
so the positive divisors of 6 are 1, 2, 3 and 6.
Proper positive divisors of 6 are 1, 2 and 3.
Now 1 + 2 + 3 = 6.
SO 6 is a Perfect Number.
First four perfect numbers are 6, 28, 496, 8128.