Rumpelstiltskin- how many guesses can the queen make

Hi can someone check over my work?

How many guesses can the queen make in order to guess the name rumpelstiltskin, if she only knows the letters?

so i thought this would be a permutation with repeting items

r u m p e ll ss tt ii k n


\(\displaystyle \L\frac{15!}{2!*2!*2!*2!}\)

\(\displaystyle \L\ =81 729 648 000\)

but thats not the answer in the back..

Thanks

Again you are correct, unless we both are misreading it.