Donald Trump is running for president, and whatever you think of his chances of picking up votes, few candidates trump The Donald on social media.

Yet there's something strange about a lot of his online fans. Only 42% of Trump’s 1.7 million followers on Facebook are American, while most come from developing nations including the Philippines, Malaysia, India, South Africa, Indonesia, and Colombia, a Vocativ analysis shows.

It's not entirely unusual for Trump to have followers in developing countries given that he is an internationally renowned business celebrity, runs the Miss Universe pageant, and has properties worldwide. But in some of the countries in which Trump has properties — Turkey, Korea, Ireland, Dubai — he doesn't have a large Facebook following.

What Trump does have is a large fan base in countries that researchers have deemed hubs for Facebook fraud. Specifically, they are home to "like farms" — services through which companies or individuals can buy Facebook likes using zombie accounts run by people who may be paid as little as $120 a year.

The grossly inflated ratio of Trump's American followers to farm-country Facebook fans also suggests that a chunk of his supporters is probably fake. One in every 27 Trump followers is from the Philippines. While presidential candidates Marco Rubio and Ted Cruz also have followers there, only one in 519 Cruz followers and one in 573 Rubio followers are from the Southeast Asian country.

Vocativ asked Michael Fire, a researcher who studies fake social-media profiles, to examine two years' worth of Facebook like activity on Trump's page, mapped in a graph pictured below. Fire said a significant portion of Trump's followers could be attributed to Facebook fraud. "If you look at Google trends, you don't see a sudden interest in …Donald Trump. So, the increase in likes looks strange," Fire said. "Moreover, the pattern of the graph also looks like it tries to avoid detection by the Facebook protection systems, because it increases slowly and then seems to stop."

An analysis of Trump's Malaysian followers revealed that some of them like more than 7,000 pages each, including pages created for brands, celebrities, and TV shows. Many of the accounts have nothing in common with one another. "If they 'like' things that contradict each other, it may be another indication that the profile is fake," Fire said.

So how much could Trump be paying for followers? On pages such as BoostLikes, $99 a month gets you 300 to 400 fans a month. Other sites charge about $15 per $1,000 likes. On the day of Trump's most recent Facebook bump, his account gained roughly 66,000 likes. If he paid $15 per 1,000 of them (which he probably didn't, because many have to be real followers, too), then the single boost would have cost him about $1,000 — pocket change to a billionaire.