Manchester United forward Cristiano Ronaldo has become the first person to have 500 million followers on Instagram. Lionel Messi is the second most-followed person with 376 million followers. Kylie Jenner comes in next, followed by Selena Gomez, Dwayne Johnson, Ariana Grande, Kim Kardashian, Beyoncé, Khloé Kardashian and Justin Bieber.