Is 8128 a perfect number?
Yes, 8128 is a perfect number, that is to day 8128 equals the sum of its proper positive divisors, i.e., the sum of its divisors excluding 8128 itself.
Indeed, 8128 = 1 + 2 + 4 + 8 + 16 + 32 + 64 + 127 + 254 + 508 + 1 016 + 2 032 + 4 064.
Note that perfect numbers are very rare: there are only 4 perfect numbers smaller than 1 000 000, viz., 6, 28, 496 and 8 128. Then, the next perfect number is already 33 550 336!
PARITY OF 8128
8128 is an even number, because it is evenly divisible by 2: 8128 / 2 = 4 064.
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Is 8128 a perfect number?
Is 8128 a Perfect Number?
A perfect number is a positive integer that is equal to the sum of its proper divisors. Proper divisors of a number are the positive divisors excluding the number itself. In order to determine whether 8128 is a perfect number or not, we need to find its proper divisors and calculate their sum.
Calculating Proper Divisors of 8128:
To find the proper divisors of 8128, we need to find all the numbers that divide 8128 evenly without leaving a remainder. Let's calculate the proper divisors step by step:
1. Start by finding the prime factorization of 8128. Prime factorization is the process of breaking down a number into its prime factors.
- Prime factors of 8128: 2 * 2 * 2 * 2 * 127 = 2^4 * 127
2. Now, we can find all the divisors of 8128 by considering all the combinations of the prime factors.
- The divisors of 8128 are: 1, 2, 4, 8, 16, 32, 127, 254, 508, 1016, 2032, 4064
3. To find the proper divisors, we exclude the number itself, which means we remove 8128 from the list of divisors.
- The proper divisors of 8128 are: 1, 2, 4, 8, 16, 32, 127, 254, 508, 1016, 2032, 4064
Calculating the Sum of Proper Divisors:
To determine if 8128 is a perfect number, we need to sum up its proper divisors and check if the sum equals 8128.
- The sum of the proper divisors of 8128 is: 1 + 2 + 4 + 8 + 16 + 32 + 127 + 254 + 508 + 1016 + 2032 + 4064 = 8128
Conclusion:
Considering the definition of a perfect number, we have found that the sum of the proper divisors of 8128 is equal to the number itself. Therefore, 8128 is indeed a perfect number.
Note:
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