He both does and doesn't have a trillion dollars.
The *valuation* of his shares puts his net worth at a trillion dollars, but that valuation can fluctuate (and deflate entirely).
This does allow him to take out tax-dodging loans based on said valuation, but he'll never hold a trillion in the bank.
If you were to count out a million seconds, it would take you 11 and a half days.
A billion seconds would take you 31.7 years.
But a trillion seconds would take 31,700 years — to reach that point today, you would have needed to start counting around the time that neanderthals went extinct.