Check whether a number is perfect or notΒΆ
Write a python function to check whether a number is perfect or not.
According to Wikipedia :
In number theory, 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
(also known as its aliquot sum).
Equivalently, a perfect number is a number that is half the
sum of all of its positive divisors (including itself).
Example :
The first perfect number is 6, because 1, 2, and 3 are its proper
positive divisors, and 1 + 2 + 3 = 6.
Equivalently, the number 6 is equal to half the sum of all
its positive divisors: ( 1 + 2 + 3 + 6 ) / 2 = 6.
The next perfect number is 28 = 1 + 2 + 4 + 7 + 14.
This is followed by the perfect numbers 496 and 8128.
def is_perfect_number(N):
sum = 0
for x in range(1, N):
if N % x == 0:
sum += x
return sum == N
# test
print(is_perfect_number(6)) # True