SpaceX’s record US$75-billion public listing has made South African-born entrepreneur Elon Musk the world’s first dollar trillionaire – but US$1-trillion is a sum so gargantuan that it’s almost impossible to comprehend.

How much is a trillion dollars? Let’s make it simple.

Start with time. If US$1 equals one second, then a million seconds works out to roughly 11 days. A billion seconds? An incredible 31 years. And a trillion seconds comes to about 31 700 years.

Put another way: if you earned $1 every second, it would take roughly 31 700 years to reach a trillion dollars.

To put that into perspective, around 31 700 years ago (circa 29 700 BCE):

The Earth was firmly in the grip of the last Ice Age;
Early modern humans were painting the first great works of cave art;
The last Neanderthals had recently vanished from Europe; and
Woolly mammoths still roamed Eurasia.

It boggles the mind.

Spend $1-million every single day and it would still take nearly 2 740 years to exhaust a trillion dollars. You’d have needed to start on the day Rome was founded in 753 BCE – before Julius Caesar, before the birth of Christ, before the fall of the Western Roman Empire – and you would only have handed over the last dollar sometime in the 1980s.

An epoch of money

Speed it up to $1-million every hour and it would still take 114 years. Even at $1-million a minute – faster than any human could physically authorise the transactions – you’d need nearly two years.

The physical comparisons are just as absurd. Lay a trillion $1 bills end to end and the line would stretch about 156 million kilometres – far enough to reach past the sun, which sits roughly 149.6 million kilometres from Earth.

And if you tried to drive the length of that line at highway speed (120km/h) without ever stopping, it would take you about 148 years to reach the end.

You get the idea. A trillion is not just a ton of money – it’s an epoch of money.