Command line to find prime factors up to about 35-digit
echo 464727894806381917382718260556330873831429153382989420435536615268075433169776375735700673656081885817695686079574546874110863931161054573908067853190417592686784819909216766687039872005727451786367 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 464727894806381917382718260556330873831429153382989420435536615268075433169776375735700673656081885817695686079574546874110863931161054573908067853190417592686784819909216766687039872005727451786367 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 464727894806381917382718260556330873831429153382989420435536615268075433169776375735700673656081885817695686079574546874110863931161054573908067853190417592686784819909216766687039872005727451786367 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 464727894806381917382718260556330873831429153382989420435536615268075433169776375735700673656081885817695686079574546874110863931161054573908067853190417592686784819909216766687039872005727451786367 | ecm -n -c 7553 43e6