Mashable:

In the tweet, Trump says that 45.6 million people watched his State of the Union address on Tuesday. So far, so good. That number checks out. 

But then he claims that's the "highest number in history."

This is something a simple Google search easily unravels. Multiple statistics tracking sites and viewership records show that Trump's first State of the Union was somewhere in the middle of the pack. The largest on record for viewership is George W. Bush's 2003 speech, which attracted 62 million viewers.

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