Command line to find prime factors up to about 20-digit
echo 662778810442043101561071402367069781834227662640943986624576683022003380908854085745851956661362736034006609162291879091592918912912932119779901958933846114762992995597245612769 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 662778810442043101561071402367069781834227662640943986624576683022003380908854085745851956661362736034006609162291879091592918912912932119779901958933846114762992995597245612769 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 662778810442043101561071402367069781834227662640943986624576683022003380908854085745851956661362736034006609162291879091592918912912932119779901958933846114762992995597245612769 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 662778810442043101561071402367069781834227662640943986624576683022003380908854085745851956661362736034006609162291879091592918912912932119779901958933846114762992995597245612769 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 662778810442043101561071402367069781834227662640943986624576683022003380908854085745851956661362736034006609162291879091592918912912932119779901958933846114762992995597245612769 | ecm -n -c 2350 3e6