[DOC] [TLE] Perfect number - Wikipedia [PAR] In number theory, a perfect number is a positive integer that is equal to the sum of 
its proper ... Equivalently, a perfect number is a number that is half the sum of all 
of its positive divisors (including itself) i.e. 1(n) ... The next perfect number is 28 
= 1 + 2 + 4 + 7 + 14. ... For 2p  1 to be prime, it is necessary that p itself be prime. [DOC] [TLE] Perfect Numbers - mathschallenge.net [PAR] The divisors of a natural number, excluding the number itself, are called the ... For 
example, the divisors of 28 are 1, 2, 4, 7, 14, and 28, so the sum of ... a perfect 
number as a number for which the sum of all its divisors is twice the number. [DOC] [TLE] Math Forum: Ask Dr. Math FAQ: Perfect Numbers [PAR] Examples: The factors of 6 are 1, 2, 3 and 6. 1 + 2 + 3 = 6. The factors of 28 are 1, 
2, 4, 7, 14 and 28. 1 + 2 + 4 + 7 + 14 = 28. The factors of 496 are 1, 2, 4, 8, 16,... [DOC] [TLE] Perfect numbers [PAR] A perfect number is defined to be one which is equal to the sum of its aliquot 
parts. The four perfect numbers 6, 28, 496 and 8128 seem to have been known 
from ancient times ... 28 = 1 + 2 + 4 + 7 + 14, ... To illustrate this Proposition 
consider 1 + 2 + 4 = 7 which is prime. ... All of these are given without any attempt 
at a proof. [DOC] [TLE] A number is called a perfect number if it equals the sum of all its ... [PAR] (1) List all the factors of 16 My answer: 1,2,4,8,16 That is correct. ... But how and 
why is 28 a perfect number. dimes are packaged 50 in a roll. quarters come 40 in 
a ... If you include the number itself as a factor, there is no answer. 2 and 3 ..... For 
example, 1123 has a digit sum of 1+1+2+3=7. ... 14 is the number, list the factors [DOC] [TLE] Prime Numbers - Advanced - Math is Fun [PAR] A Prime Number can be divided evenly only by 1 or itself. ... Example: 28 (proper 
factors: 1,2,4,7,14) is also a Perfect number, because 1+2+4+7+14=28. ... These 
are now called Euclid numbers and Euler proved that all even Perfect numbers ... 
the sum of three odd primes: Vinogradov's theorem shows this true of all except... [DOC] [TLE] solution [PAR] 1. (20 points) We call a positive integer perfect if it equals the sum of its positive 
divisors ... We have that 28 = 2  2  7, so the positive divisors of 28 are 1, 2, 4, 7, 
and 14. ... (b) Prove that if 2p  1 is prime, then 2p1(2p  1) is a perfect number. 
The positive divisors of 2p1(2p  1) other than itself for 2p  1 prime are all the. [DOC] [TLE] Numbers, Part IV - Math Goodies [PAR] 1-- A perfect number, N, is a number equal to the sum of all its proper ... N, is 
perfect if it is the sum of all its factors/divisors, not including the number itself. ... 
28 = 1 + 2 + 4 + 7 + 14 and 1/1 + 1/2 + 1/4 + 1/7 + 1/14 + 1/28 = 2 and 1^3 + 3^3 = 
28. .... The squares of these numbers are simultaneously square and triangular. [DOC] [TLE] Perfect Numbers | List of Perfect Numbers | Math@TutorVista.com [PAR] Proper divisors include all the divisors of a number except the number itself. ... A 
perfect number is a number equal to the sum of all of its proper divisors. Example 
... Step1: Divisors of 28 are 1, 2, 4, 7, 14

Question: A perfect number is the sum of all of these except itself; for example, 28 is the sum of 1, 2, 4, 7 & 14
Answer: Its factors