Command line to find prime factors up to about 50-digit
echo 7767589884898905584453846627616528735466833665717627569798152437068183984890392285268361811654098469581336926528022496076374393063 | ecm -n -c 6373 43e6
Command line to find prime factors up to about 55-digit
echo 7767589884898905584453846627616528735466833665717627569798152437068183984890392285268361811654098469581336926528022496076374393063 | ecm -n -c 17395 11e7
Command line to find prime factors up to about 60-digit
echo 7767589884898905584453846627616528735466833665717627569798152437068183984890392285268361811654098469581336926528022496076374393063 | ecm -n -c 41906 26e7
Command line to find prime factors up to about 65-digit
echo 7767589884898905584453846627616528735466833665717627569798152437068183984890392285268361811654098469581336926528022496076374393063 | ecm -n -c 69386 85e7