Command line to find prime factors up to about 45-digit
echo 584007835215841023914570617715978472185467226928522854270402554909781892083903707220755763820847809181447063739979202027382276323332414501651001415039887883735570574048322709 | ecm -n -c 3928 11e6
Command line to find prime factors up to about 50-digit
echo 584007835215841023914570617715978472185467226928522854270402554909781892083903707220755763820847809181447063739979202027382276323332414501651001415039887883735570574048322709 | ecm -n -c 7459 43e6
Command line to find prime factors up to about 55-digit
echo 584007835215841023914570617715978472185467226928522854270402554909781892083903707220755763820847809181447063739979202027382276323332414501651001415039887883735570574048322709 | ecm -n -c 17750 11e7
Command line to find prime factors up to about 60-digit
echo 584007835215841023914570617715978472185467226928522854270402554909781892083903707220755763820847809181447063739979202027382276323332414501651001415039887883735570574048322709 | ecm -n -c 42014 26e7