Popsugar Celebrity Celebrity Instagrams John Legend Celebrates 42nd Birthday With Maths Competition Chrissy Teigen Went All Out For John Legend's Birthday Maths-Off Competition — See the Pics! 29 December 2020 by Yerin Kim View On One Page Photo 5 of 6 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 5 Previous Next Start Slideshow Celebrity InstagramsJen AtkinCelebrity BirthdaysChrissy TeigenJohn Legend