Answer
780 is not perfect because:
1 + 2 + 3 + 4 + 5 + 6 + 10 + 12 + 13 + 15 + 20 + 26 + 30 + 39 + 52 + 60 + 65 + 78 + 130 + 156 + 195 + 260 + 390 ≠ 780
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Answer
780 is not perfect because:
1 + 2 + 3 + 4 + 5 + 6 + 10 + 12 + 13 + 15 + 20 + 26 + 30 + 39 + 52 + 60 + 65 + 78 + 130 + 156 + 195 + 260 + 390 ≠ 780