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A number n is said to be perfect if t...

A number `n` is said to be perfect if the sum of all its divisors (excluding `n` itself) is equal to `n` . An example of perfect number is (a) 6 (b) 9 (c) 15 (d) 21

A

9

B

15

C

21

D

6

Text Solution

Verified by Experts

The correct Answer is:
D
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