Command line to find prime factors up to about 40-digit
echo 191884548366709150431536014176499504017574488166176366425076129509061213590000797073040315891921077084427847623834050555538185693 | ecm -n -c 1836 3e6
Command line to find prime factors up to about 45-digit
echo 191884548366709150431536014176499504017574488166176366425076129509061213590000797073040315891921077084427847623834050555538185693 | ecm -n -c 4368 11e6
Command line to find prime factors up to about 50-digit
echo 191884548366709150431536014176499504017574488166176366425076129509061213590000797073040315891921077084427847623834050555538185693 | ecm -n -c 7534 43e6
Command line to find prime factors up to about 55-digit
echo 191884548366709150431536014176499504017574488166176366425076129509061213590000797073040315891921077084427847623834050555538185693 | ecm -n -c 17766 11e7