How to pronounce “345” in English

Spain, 345.

2018 the cost of treating obesity related illness in the United States will be 345 billion dollars a year."

So if it was, you know, 12.345678, it would just go to 12.345.

Well, today I'd like to introduce 12,345 of these ideas,

But I would imagine, I know many places I've been, people inside are screaming, "I have to get out of this meeting and there's 345 PowerPoint slides for a one hour presentation."

So, if it was you know 12.345 678 it would just go to 12.345