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An example - the divisors of 28 are 1 -2 - 4 - 7 - 14 and 28. In other words 1+2+4+7+14 = 28
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How is 20 a perfect number?
It isn't a perfect number.A perfect number is a number which is the sum of its proper divisors (including 1, but excluding itself).The divisors of 20 are 1, 2, 4, 5, 10.1 + 2 + 4 + 5 + 10 = 22 => 20 is not a perfect number.An example of a perfect number is 28:The divisors of 28 are 1, 2, 4, 7, 141 + 2 + 4 + 7 + 14 = 28 => 28 is a perfect number.
Is 8128 a abundant deficient or perfect number?
abundant since sum of divisors is 16256
Why 21 is not a perfect number?
First, you want to know the definition of a perfect number: A perfect number is an integer which is equal to the sum of all its positive integer divisors that are less than itself. Example: The positive integer divisors of 6, less than 6, are 1, 2, and 3. The sum of those divisors is 1 + 2 + 3 = 6. Therefore, 6 is a perfect number. Now, 21 does not meet this definition and therefore is not a perfect number. Let's try it. There are three positive divisors of 21, namely, 1, 3, and 7, that are less than 21, itself. (There are no others.) But the sum of these divisors is 1 + 3 + 7 = 11, which is not equal to 21. Therefore, we confirm that 21 is not a perfect number.
How can you tell if a number is abundant perfect or deficient?
Find the sum of the proper divisors of that number.a perfect number equals the sum of its proper divisorsa deficient number is greater than the sum of its proper divisorsan abundant number is less than the sum of its proper divisors
Why are no prime numbers perfect numbers?
Prime numbers have two factors. The sum of their proper divisors is always 1.
Is 8 a perfect number?
A perfect number is the sum of its divisors; for example 6 is a perfect number because the sum of its divisors is 6 (1 + 2 + 3). The sum of the divisors of 8 is 7 (1 + 2 + 4), so 8 is not a perfect number.
What is a perfect Abundant Or dificient number?
A perfect number equals the sum of its proper divisors. A deficient number is greater than the sum of its proper divisors. An abundant number is less than the sum of its proper divisors. Proper divisors of a number do not include the number itself.
What is the seventh perfect number?
a perfect number is defined as a positive integer which is the sum of its proper positive divisors, that is, the sum of the positive divisors excluding the number itself 137,438,691,328 is the 7th perfect number.
What is a perfect number and give an example of one?
A perfect number is equal to the sum of its proper divisors (the factors excluding the number itself.) 6 is a perfect number. Its proper divisors are 1, 2 and 3.
What is a picture perfect number?
In math a picture perfect number is a number which is the sum of its proper divisors.
Why are perfect numbers perfect?
A perfect number is only classified as a perfect number because all of its proper divisors add up to itself. For example, the proper divisors of six are one, two and three. Those numbers added together equal six. Therefore, six is a perfect number.
How is 20 a perfect number?
It isn't a perfect number.A perfect number is a number which is the sum of its proper divisors (including 1, but excluding itself).The divisors of 20 are 1, 2, 4, 5, 10.1 + 2 + 4 + 5 + 10 = 22 => 20 is not a perfect number.An example of a perfect number is 28:The divisors of 28 are 1, 2, 4, 7, 141 + 2 + 4 + 7 + 14 = 28 => 28 is a perfect number.
Is 8128 a abundant deficient or perfect number?
abundant since sum of divisors is 16256
Why 21 is not a perfect number?
First, you want to know the definition of a perfect number: A perfect number is an integer which is equal to the sum of all its positive integer divisors that are less than itself. Example: The positive integer divisors of 6, less than 6, are 1, 2, and 3. The sum of those divisors is 1 + 2 + 3 = 6. Therefore, 6 is a perfect number. Now, 21 does not meet this definition and therefore is not a perfect number. Let's try it. There are three positive divisors of 21, namely, 1, 3, and 7, that are less than 21, itself. (There are no others.) But the sum of these divisors is 1 + 3 + 7 = 11, which is not equal to 21. Therefore, we confirm that 21 is not a perfect number.
Is 214 abundant deficient or perfect?
A perfect number is a number which is the sum of it's positive proper divisors. 214 has divisors: 1, 2, 107 1 + 2 + 107 = 110 != 214 Thus 214 is not a perfect number The first 4 perfect numbers are: 6, 28, 496 and 8128.
What is the perfect number and what is the perfect number after six?
A perfect number is a number, which, when adding all of its proper divisors (all divisors except himself) give the number itself Divisors of 6: 1,2,3 ------>1+2+3=6 The next proper number is 28 Divisors of 28:1,2,4,7,14 -------> 1+2+4+7+14=28 All perfect numbers found so far are found using this formula: 2^(p-1)*((2^p)-1), where p, and ((2^p)-1) are prime numbers
How can you tell if a number is abundant perfect or deficient?
Find the sum of the proper divisors of that number.a perfect number equals the sum of its proper divisorsa deficient number is greater than the sum of its proper divisorsan abundant number is less than the sum of its proper divisors
