Command line to find prime factors up to about 40-digit
echo 3663098565111345395412929971728350097530716199796536338138921821753864966157300030614431362264492489238686784881314038315456171995557481 | ecm -n -c 956 3e6
Command line to find prime factors up to about 45-digit
echo 3663098565111345395412929971728350097530716199796536338138921821753864966157300030614431362264492489238686784881314038315456171995557481 | ecm -n -c 4079 11e6
Command line to find prime factors up to about 50-digit
echo 3663098565111345395412929971728350097530716199796536338138921821753864966157300030614431362264492489238686784881314038315456171995557481 | ecm -n -c 7464 43e6
Command line to find prime factors up to about 55-digit
echo 3663098565111345395412929971728350097530716199796536338138921821753864966157300030614431362264492489238686784881314038315456171995557481 | ecm -n -c 17744 11e7