Command line to find prime factors up to about 45-digit
echo 29297402016470524234096481937774452825853317683256295975854623540072654392659095875611433521676001164170111844716196224386736672898007231 | ecm -n -c 3974 11e6
Command line to find prime factors up to about 50-digit
echo 29297402016470524234096481937774452825853317683256295975854623540072654392659095875611433521676001164170111844716196224386736672898007231 | ecm -n -c 7469 43e6
Command line to find prime factors up to about 55-digit
echo 29297402016470524234096481937774452825853317683256295975854623540072654392659095875611433521676001164170111844716196224386736672898007231 | ecm -n -c 17752 11e7
Command line to find prime factors up to about 60-digit
echo 29297402016470524234096481937774452825853317683256295975854623540072654392659095875611433521676001164170111844716196224386736672898007231 | ecm -n -c 42014 26e7