Command line to find prime factors up to about 35-digit
echo 99199018036574176028646980289867574094544828753519594080981747346919975752061110460212979741493363451746059921544994228560919814158223128194594538809139908884768901170633433423243 | ecm -n -c 828 1e6
Command line to find prime factors up to about 40-digit
echo 99199018036574176028646980289867574094544828753519594080981747346919975752061110460212979741493363451746059921544994228560919814158223128194594538809139908884768901170633433423243 | ecm -n -c 2337 3e6
Command line to find prime factors up to about 45-digit
echo 99199018036574176028646980289867574094544828753519594080981747346919975752061110460212979741493363451746059921544994228560919814158223128194594538809139908884768901170633433423243 | ecm -n -c 4479 11e6
Command line to find prime factors up to about 50-digit
echo 99199018036574176028646980289867574094544828753519594080981747346919975752061110460212979741493363451746059921544994228560919814158223128194594538809139908884768901170633433423243 | ecm -n -c 7553 43e6