Command line to find prime factors up to about 20-digit
echo 1025350232777767894657857694224037906084707953452549927614176139794019761184051887773588580834083860417243760161496256204277649426690598247446485244284214565467839 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 1025350232777767894657857694224037906084707953452549927614176139794019761184051887773588580834083860417243760161496256204277649426690598247446485244284214565467839 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 1025350232777767894657857694224037906084707953452549927614176139794019761184051887773588580834083860417243760161496256204277649426690598247446485244284214565467839 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 1025350232777767894657857694224037906084707953452549927614176139794019761184051887773588580834083860417243760161496256204277649426690598247446485244284214565467839 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 1025350232777767894657857694224037906084707953452549927614176139794019761184051887773588580834083860417243760161496256204277649426690598247446485244284214565467839 | ecm -n -c 2350 3e6