added perfect number implementation

Author: namitmalasi

PerfectNumber.js

@@ -0,0 +1,21 @@
+// Perfect number is a positive integer that is equal to the sum of its positive divisors, excluding
+// the number itself. For instance, 6 has divisors 1, 2 and 3 (excluding itself),
+// and 1 + 2 + 3 = 6, so 6 is a perfect number.
+
+function isPerfectNumber(number) {
+  let temp = number;
+  let sum = 0;
+  for (let i = 1; i <= temp / 2; i++) {
+    if (temp % i === 0) sum += i;
+  }
+  if (sum === number) {
+    return `${number} is a Perfect number.`;
+  } else {
+    return `${number} is not a Perfect number.`;
+  }
+}
+
+console.log(isPerfectNumber(6));
+console.log(isPerfectNumber(28));
+console.log(isPerfectNumber(5));
+console.log(isPerfectNumber(496));