Therefore in particular the digital root of every even perfect number other than 6 is 1 .
Every even perfect number ends in 6 or 28 , base ten ; and , with the only exception of 6 , ends in 1 , base 9 .
In particular the digital root of every even perfect number other than 6 is 1 .
Every even perfect number ends in 6 or 28 , base ten ; and , with the only exception of 6 , ends in 1 , base 9 .