We hear about trillions all the time now, but the number is beyond human comprehension.

April 6, 2021

Last year, as the rich grew richer while the poor grew only in number, speculation began about who would become the first trillionaire. (Jeff Bezos was the clear front-runner.)

It was a big moment for the word “trillion,” which came into full flower over the past year, mostly as a number that gets thrown around with casual disregard for all those zeros (12) — particularly in the United States when talking about stimulus dollars or the budget deficit or the national debt or the four trillion-dollar companies of the tech industry.

But by the end of 2020, when Congress passed a second round of stimulus just shy of $1 trillion, at $900 billion, the amount had become, eh, whatever. Many economists and a good portion of the public believed a trillion wasn’t enough. (Not the Arkansas Democrat-Gazette editorial desk, which recently characterized the move as that of a, “spendthrift nation, a trillion here, a trillion there.”)

Before the pandemic, “trillion” was a word more commonly uttered by astrophysicists and obscure central bankers, not everyday Americans. That it has gained such widespread usage during a period of staggering unemployment and economic ruin is but one oddity of our moment.

And while it may be a number the public has become accustomed to, it’s also a number beyond all human comprehension. How to visualize a trillion? It’s not like visualizing a million. It’s not even like visualizing a billion.

Jerry Pacheco, a columnist for The Albuquerque Journal, recently put the figure in context. “If you spent $40 per second, around the clock, it would take you 289 days to exhaust a billion dollars,” he wrote. “If you did the same thing with a trillion dollars, it would take you 792.5 years to go broke.”

Put another way, Mr. Pacheco explained, a trillion dollars laid end to end “would stretch for 96,906,656 miles, a distance farther than the sun.”

Of course, that comparison may not be much help for the human brain, which can have a hard time grasping gigantic numbers with which mere mortals largely lack direct experience. As Scientific American put it a few years ago: “Citizens emotionally undeterred by billions and trillions are nonetheless likely to be ill-equipped for meaningful analysis.” You get weird cognitive dissonances. Hear $3 trillion enough times and $2 billion may start to sound puny.

Those of a certain age will remember when “million” was the numerical measure for a whopping figure. “So-and-so is a millionaire,” you might whisper. There were songs like “The Millionaire” by Dr. Hook, movies like “Brewster’s Millions” (based on a 1902 novel of the same name), million-man marches, sweepstakes promoting the idea of instantly becoming one, a long-running hit game show, “Who Wants to Be a Millionaire?”

That show debuted in 1999. But it was around the turn of the new century, and concurrent with the rise of Silicon Valley fortunes, when a few zeros got added in the popular imagination. Billion replaced million as the impossibly large yet routinely cited number.

Imagine bestowing a TV show with the title “Billions” in 1986 or 1996 — it would have seemed hubristic if not wholly fictional. By 2016, when “Billions” debuted on Showtime, it captured the zeitgeist. Forbes called the 2010s “A Decade of Billionaires,” and indeed, so many were minted in those years that the count nearly doubled between 2008 and 2020. There are 2,095 billionaires today, according to the publication.

Unless you were a Wall Street quant, however, trillion had long felt remote. It was like gazillion: a joke number. “The Trillionaire Next Door” is what Andy Borowitz, the humorist, titled his spoof 2000 book about day trading. In a radio appearance at the time, Mr. Borowitz said he wrote it because, “People aim too low. I mean, a millionaire? Please.”

That same year — 2000 — the word “trillion” appeared in The New York Times 856 times.

In the first three months of 2021, “trillion” has already appeared in this paper 723 times.

Much of that usage is in reference to the $1.9 trillion stimulus bill that Congress passed in March. (Too much? Too little? The debate goes on). Faster than you could say, er, “1 followed by 12 zeros,” the Biden administration had already turned its attention to an infrastructure bill it hopes to pass later this year. The amount? $2.2 trillion.

Indeed, it’s not just money. The United Nations Environmental Program’s worldwide tree-planting movement, nicknamed the “billion tree campaign” when it started in 2006, has become the trillion-tree campaign. Some artificial intelligence executives are planning for a future of trillions of internet-connected devices. And scientists are already talking about Brood X, a colony of cicadas that will emerge from their 17-year hibernation to flood the United States this spring.

What’s the high end for the number of cicadas we can expect? One guess.