Command line to find prime factors up to about 20-digit
echo 39234349662209658791480376778732854742005143556242548574854184085364695615460049980440362131507169768084663056542208916055640984224960218782975301012422338283325189637342769111 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 39234349662209658791480376778732854742005143556242548574854184085364695615460049980440362131507169768084663056542208916055640984224960218782975301012422338283325189637342769111 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 39234349662209658791480376778732854742005143556242548574854184085364695615460049980440362131507169768084663056542208916055640984224960218782975301012422338283325189637342769111 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 39234349662209658791480376778732854742005143556242548574854184085364695615460049980440362131507169768084663056542208916055640984224960218782975301012422338283325189637342769111 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 39234349662209658791480376778732854742005143556242548574854184085364695615460049980440362131507169768084663056542208916055640984224960218782975301012422338283325189637342769111 | ecm -n -c 2350 3e6