1 in 10 billion trillion is some pretty serious odds.
It does get more complicated if we factor in life happening quickly enough without an extinction event.
But after looking at images like this there is just NO WAY we are the only ones.
It's just too arrogant to think we currently can place odds on all the important events necessary for us or something like us to come into being. At the time this equation was devised, I'm not even sure they understood how crazy lucky the development of mitochondria was.
In reality, we just don't know the many factors that might've affected our outcome. Also, it's just pure lottery falacy to reason about the statics that specifically "we" exist. If the odds for some strange reason settled out around about 1 of there being a single sentient species in our universe, that species would come to reason about itself and produce the same long odds of their existence. It's a longshot that a specific someone wins the lottery twice. It is a statistical inevitability that someone will win twice.
Whoever they are, they can't alienate themselves from being the one despite all the statistical huffing and puffing they can conjure. We will only know how special we are when we find another or once we have surveyed enough planets in depth.