Command line to find prime factors up to about 20-digit
echo 1046559561437662561528732135002306101203786406077470674129639406365392629233852313443819288968279705505392714731162791475763053482711616108659000663178562737278453 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 1046559561437662561528732135002306101203786406077470674129639406365392629233852313443819288968279705505392714731162791475763053482711616108659000663178562737278453 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 1046559561437662561528732135002306101203786406077470674129639406365392629233852313443819288968279705505392714731162791475763053482711616108659000663178562737278453 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 1046559561437662561528732135002306101203786406077470674129639406365392629233852313443819288968279705505392714731162791475763053482711616108659000663178562737278453 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 1046559561437662561528732135002306101203786406077470674129639406365392629233852313443819288968279705505392714731162791475763053482711616108659000663178562737278453 | ecm -n -c 2350 3e6