Using PHP:

Write a function that:

Given a numerical parameter in input, outputs:

If the number is a perfect number, and

The divisors and proof of such conclusion

NOTE: A perfect number is equal to the sum of its proper divisors

Example:

If input parameter is $6,$ output is "Yes, this is a perfect number. Proof: $1+2+3=6"$

If input parameter is $3,$ output is $"$No$,$ this is not a perfect number. Proof: $1!=3"$

Write a "tester function" that:

Given a specific subset of inputs, tests the function described above $($point $1).$

Example, in pseudo code:

tester$\_$function:

is output from is$\_$perfect$\_$number$(6)$ equal to $"..."?$ If yes, test passed

is output from is$\_$perfect$\_$number$()$ equal to $"..."?$ If yes, test passed

$..$