find the sum of the smallest three prime factors of 6^22-1

• first take the prime factors of the number 22
  ie, 22 = 2*11
  now consider, 6^2-1 = 35 = 5 * 7
  so, the first two prime factors are 5 and 7
  e.g, 6^(2*2)-1 = 1295 has a factors of 5 and 7, so on
  it is true for all the even power of 6
  
  for the next number you have to check the prime factors of 6^11 , which is not possible to do. so there is other way to find the nest number
  there is a property of prime numbers
  i.e, (x^(p-1)-1 )/ p = 0
  where p is the prime number and x is any number less than p
  
  in this case x=6 and p = 22+1 = 23
  
  so the sum of all the prime numbers will be = 5+7+23 = 35
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