That's what the Obama Care website (which does not work) contains. 500 million lines of code.
A Slate article referring to a story in the New York Times, walks us through the mess that is Healthcare.gov. "Dan Check, Slate’s vice president for technology, puts it this way: "If you contract something out and get 500 million lines of code back, there’s no way it’s going to work correctly."
..."A number like 500 million suggests the Healthcare.gov contractors may be writing their own code in many places where they'd be better off relying on open-source external libraries. They may also be solving problems via copy-and-paste rather than more elegant programming techniques such as inheritance or polymorphism."
"So if, as the Times piece suggests, the contractors responsible for fixing HealthCare.gov are already thinking about the task in terms of millions of lines of code, the situation may be even worse than we thought. It’s not just that the problem is large in scope—it’s that the people in charge of fixing it are going about it all wrong."
There is nothing more to add except weeks of work to get a viable site online. It might be better to bring in an entirely new group of actual programmers to start from scratch rather than give the controls back to the contractors hired in the first place. If their judgment is as poor when selecting "a surge of technicians" then it may never get up and running.