Since you ask....
There are a couple of reasons no one's answering. One is that your question is asked fairly often, and some of us get weary of answering the same question repeatedly when you could easily do a site search on your own.
Another reason is that you're asking the equivalent of "How long is a piece of string?" Realistic answers from experienced riders will tend to begin and end with "It depends...." because it does, in fact, depend on a variety of factors. You can make it in 6 weeks if you push hard, stick to the main routes, and have no major breakdowns or accidents (and have no particular interest in doing much besides ride every day)...which is another way of saying, "it depends."
A third reason is that you say "a trip like that," but fail to state where you're starting.
Hope that's helpful.