Command line to find prime factors up to about 35-digit
echo 463342040697389197322032087129438789877693680287793864518201111816559729047728130782585261021820792907956389519728150267989170749064273031304390131933617966183812600801956446744875697222823118388981 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 463342040697389197322032087129438789877693680287793864518201111816559729047728130782585261021820792907956389519728150267989170749064273031304390131933617966183812600801956446744875697222823118388981 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 463342040697389197322032087129438789877693680287793864518201111816559729047728130782585261021820792907956389519728150267989170749064273031304390131933617966183812600801956446744875697222823118388981 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 463342040697389197322032087129438789877693680287793864518201111816559729047728130782585261021820792907956389519728150267989170749064273031304390131933617966183812600801956446744875697222823118388981 | ecm -n -c 7553 43e6