Command line to find prime factors up to about 35-digit
echo 2212335135020946316160414768197269893460057280688580627231004642405276317140391110378099251944153412560142783598642235694078247389647383102587696871604753413116807044468713058920480051162203 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 2212335135020946316160414768197269893460057280688580627231004642405276317140391110378099251944153412560142783598642235694078247389647383102587696871604753413116807044468713058920480051162203 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 2212335135020946316160414768197269893460057280688580627231004642405276317140391110378099251944153412560142783598642235694078247389647383102587696871604753413116807044468713058920480051162203 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 2212335135020946316160414768197269893460057280688580627231004642405276317140391110378099251944153412560142783598642235694078247389647383102587696871604753413116807044468713058920480051162203 | ecm -n -c 7553 43e6