Command line to find prime factors up to about 45-digit
echo 12304718427269283800902907487934827867943758170285765616212565770340367363761946855762373015366862036631276682662670554821256333345435997 | ecm -n -c 3961 11e6
Command line to find prime factors up to about 50-digit
echo 12304718427269283800902907487934827867943758170285765616212565770340367363761946855762373015366862036631276682662670554821256333345435997 | ecm -n -c 7465 43e6
Command line to find prime factors up to about 55-digit
echo 12304718427269283800902907487934827867943758170285765616212565770340367363761946855762373015366862036631276682662670554821256333345435997 | ecm -n -c 17751 11e7
Command line to find prime factors up to about 60-digit
echo 12304718427269283800902907487934827867943758170285765616212565770340367363761946855762373015366862036631276682662670554821256333345435997 | ecm -n -c 42014 26e7