Command line to find prime factors up to about 20-digit
echo 1222083427034706903773029817610399404719151533461635367757974162856636259210681170667958475510140547632037054709315922473113662735165663173 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 1222083427034706903773029817610399404719151533461635367757974162856636259210681170667958475510140547632037054709315922473113662735165663173 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 1222083427034706903773029817610399404719151533461635367757974162856636259210681170667958475510140547632037054709315922473113662735165663173 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 1222083427034706903773029817610399404719151533461635367757974162856636259210681170667958475510140547632037054709315922473113662735165663173 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 1222083427034706903773029817610399404719151533461635367757974162856636259210681170667958475510140547632037054709315922473113662735165663173 | ecm -n -c 2350 3e6