Command line to find prime factors up to about 20-digit
echo 5551272940715646555535084520808898040849411028300689833670494145896456597568585236636423257021026771606665354250412985260440425959906177808551551691676508815771777 | ecm -n -c 74 11e3
Command line to find prime factors up to about 25-digit
echo 5551272940715646555535084520808898040849411028300689833670494145896456597568585236636423257021026771606665354250412985260440425959906177808551551691676508815771777 | ecm -n -c 214 5e4
Command line to find prime factors up to about 30-digit
echo 5551272940715646555535084520808898040849411028300689833670494145896456597568585236636423257021026771606665354250412985260440425959906177808551551691676508815771777 | ecm -n -c 430 25e4
Command line to find prime factors up to about 35-digit
echo 5551272940715646555535084520808898040849411028300689833670494145896456597568585236636423257021026771606665354250412985260440425959906177808551551691676508815771777 | ecm -n -c 904 1e6
Command line to find prime factors up to about 40-digit
echo 5551272940715646555535084520808898040849411028300689833670494145896456597568585236636423257021026771606665354250412985260440425959906177808551551691676508815771777 | ecm -n -c 2350 3e6