# number=int(input("enter a number"))
# i=1
# sum=0
# while (i<number):
#     if (number%i==0):
#         sum=sum+i
#     i=i+1
# if (sum==number):
#     print("it is perfact number",number) 
# else:
#     print("it is not prefact number",number)   


# only 6,28 is prefact number