According to Forbes, there are more than 1,800 billionaires in the world, with a combined net worth of $6.48T. While some of these are well-known, most aren't. But after reading this you'll know a few more. Yahoo dove in and compiled a list of five Forbes billionaire entrants you might not have seen coming.

1. Vladimir Putin

One of Russia's largest foreign investors, Bill Browder, says he believes Putin’s net worth is $200B. Lower estimates put his net worth at $40B, but that still makes him one of the richest people in the world (although officially Putin claims a net worth of no more than $500k).

2. Bhumibol Adulyadej

Born in the US, King Adulyadej of Thailand is estimated to be worth $30B, making him the second-richest world leader (behind Putin). He's also reigned as king for almost 70 years, which is equally impressive.

3. Amancio Ortega

Amancio founded the clothing giant Zara and is worth a mind-blowing $67B. He even briefly overtook Bill Gates as the world's richest person in 2015, but his reign was short lived (unlike Bhumibol's) and he soon fell back to second place.

4. Michael Jordan

Michael made $110M in 2015, making him the highest-paid retired athlete. And he just makes the billionaire cut—Forbes says he is worth $1.1B.

5. Alexandra Andresen

Alexandra received a nice present from her father in 2007: $1.2B. Not bad, right? At just 19 years old, this Norwegian heiress to a family tobacco empire is the youngest billionaire in the world.