Command line to find prime factors up to about 35-digit
echo 117833390761822206781504235853702940398633422674715455907712487569609504674353029127577678760477779626680339767620241534635122222619356307811633522977634813958958846128976560370183 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 117833390761822206781504235853702940398633422674715455907712487569609504674353029127577678760477779626680339767620241534635122222619356307811633522977634813958958846128976560370183 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 117833390761822206781504235853702940398633422674715455907712487569609504674353029127577678760477779626680339767620241534635122222619356307811633522977634813958958846128976560370183 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 117833390761822206781504235853702940398633422674715455907712487569609504674353029127577678760477779626680339767620241534635122222619356307811633522977634813958958846128976560370183 | ecm -n -c 7553 43e6