Command line to find prime factors up to about 35-digit
echo 5720465739936398176890919414274560939669337112716312236128114585613248703543589259794005680091787465055371925452879604712537191974447480673505568720894369795477935526658778484243042263547 | ecm -n -c 825 1e6
Command line to find prime factors up to about 40-digit
echo 5720465739936398176890919414274560939669337112716312236128114585613248703543589259794005680091787465055371925452879604712537191974447480673505568720894369795477935526658778484243042263547 | ecm -n -c 2336 3e6
Command line to find prime factors up to about 45-digit
echo 5720465739936398176890919414274560939669337112716312236128114585613248703543589259794005680091787465055371925452879604712537191974447480673505568720894369795477935526658778484243042263547 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 5720465739936398176890919414274560939669337112716312236128114585613248703543589259794005680091787465055371925452879604712537191974447480673505568720894369795477935526658778484243042263547 | ecm -n -c 7553 43e6