One of the tougher math puzzles I've solved

I got this puzzle from Facebook friend, and spent a good hour solving it. I'm sure there's some people here smarter than I who can make quick work of it though.(Note: I'm adding in all of the examples that my friend had answered before I started trying to solve it, just to be fair)

The rules are simple. You can either give me an expression that I will solve to help you figure out the answer, or you can solve the riddle.

Here are the initial examples:
5+4x3=101
7+3x12=211
5+6x4=45
1+5x32=321
6+4=22
2x5+2=22
1+3+11=22
7x6/3=22

What are you looking for? 403384+29x999=?????

Extra examples:
4+6=14
1+4x3=31
2+6+2=14
4x3=110
1+1=11
4x3=110
3x4=30
4+0=undefined

BONUS! another problem to solve if you so choose:
156619936546553125594870764260+36*8888888888888888888=????