Given a deck of $$52$$ cards with numbers $$1,2,\ldots,52$$ written on them, one number per card. The deck is shuffled and $$13$$ cards are chosen at random from the shuffled deck and thrown away, without noting the numbers on them. From the remaining $$39$$ cards, one card is chosen at random. If the probability that the number on this card is a multiple of $$13$$ is $$\frac{m}{n}$$, where $$m,n$$ are integers with no common divisor other than $$1$$, then $$m+n$$ equals $$\underline{\qquad}$$.