Command line to find prime factors up to about 20-digit
echo 85554871304881673906236741879857956986265777745068824160291811708188532050382981365896551704732849176081698646674868720629221847520780705667732642190159149 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 85554871304881673906236741879857956986265777745068824160291811708188532050382981365896551704732849176081698646674868720629221847520780705667732642190159149 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 85554871304881673906236741879857956986265777745068824160291811708188532050382981365896551704732849176081698646674868720629221847520780705667732642190159149 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 85554871304881673906236741879857956986265777745068824160291811708188532050382981365896551704732849176081698646674868720629221847520780705667732642190159149 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 85554871304881673906236741879857956986265777745068824160291811708188532050382981365896551704732849176081698646674868720629221847520780705667732642190159149 | ecm -n -c 2350 3e6