These numbers can be generated by adding successive powers of two until the sum is prime and then multiplying that prime time
These numbers can be generated by adding successive powers of two until the sum is prime and then multiplying that prime times the last number added. That method is the only successful one ever used to find these numbers. That method, stated by Euclid [YOO-klid], gives the relationship between these numbers and Mersenne [mer-sen] numbers. These whole numbers, which are not superabundant or deficient, have no known odd examples. Name these numbers that equal the sum of their proper divisors.
These numbers can be generated by adding successive powers of two until the sum is prime and then multiplying that prime times the last number added.