Congrats on your success as an entrepreneur. 13 years means you did well at it. Speaking from experience, I won't sugar coat it, you're not hireable. 13 years as a startup CTO/CEO says you're not used to having a boss. Corp jobs are all about stfu and doing what you're told. Most hiring managers will pass on you for someone that's spent X years in a corp most similar to theirs.
That said, it's possible. It's usually someone you know really well that trusts you that will get you back in the game. Or companies known to hire founders, rippling comes to mind.