Command line to find prime factors up to about 20-digit
echo 1448655020660411709321686029932904914892812371603489889670419419960086718622809920923633397014146921840330621282015047668861645904218955937822148407174568592627956473581 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 1448655020660411709321686029932904914892812371603489889670419419960086718622809920923633397014146921840330621282015047668861645904218955937822148407174568592627956473581 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 1448655020660411709321686029932904914892812371603489889670419419960086718622809920923633397014146921840330621282015047668861645904218955937822148407174568592627956473581 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 1448655020660411709321686029932904914892812371603489889670419419960086718622809920923633397014146921840330621282015047668861645904218955937822148407174568592627956473581 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 1448655020660411709321686029932904914892812371603489889670419419960086718622809920923633397014146921840330621282015047668861645904218955937822148407174568592627956473581 | ecm -n -c 2350 3e6