Command line to find prime factors up to about 35-digit
echo 3363923496440831483891694000894021827833743546984106810528636505958272354825128519190170310238343247912052414855642483630605978651815348100699968565062904655999667579400028955957473191 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 3363923496440831483891694000894021827833743546984106810528636505958272354825128519190170310238343247912052414855642483630605978651815348100699968565062904655999667579400028955957473191 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 3363923496440831483891694000894021827833743546984106810528636505958272354825128519190170310238343247912052414855642483630605978651815348100699968565062904655999667579400028955957473191 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 3363923496440831483891694000894021827833743546984106810528636505958272354825128519190170310238343247912052414855642483630605978651815348100699968565062904655999667579400028955957473191 | ecm -n -c 7553 43e6