Just behind the Telmex and America Movil CEO is Microsoft boss Bill Gates, with $62.4billion.
Completing the top five are investor Warren Buffett, IKEA owner Ingvar Kamprad of Sweden and Louis Vuitton and Christian Dior exec Bernard Arnault of France.
The richest woman in the world, Christy Ruth Walton, is also on the list, at the No. 14 spot.
Walton, who inherited her husband John’s stake in Wal-Mart after his death in 2005, takes home about $24.9billion.
Her brothers-in-law, James C. and Samuel R. Walton, sons of the big box store’s founder Sam M. Walton, also appear on the list at Nos. 17 and 18, respectively.
Another set of brothers, oil billionaires David and Charles Koch, , are at Nos. 8 and 9.
The Koch’s created headlines in February after putting up $100million to get President Obama out of the White House.
CEO of Oracle Corp Larry Ellison is at No. 7 with $38billion, and Las Vegas Sands tycoon Sheldon Adelson is at no. 13 with $25.7billion.
Facebook founder and CEO Mark Zuckerberg, whose fortune is estimated to be just under $20billion, was a notable absentee from the list.
The world’s richest:
1. Carlos Slim, Telmex and America Movil – $68.5billion
2. Bill Gates, Microsoft – $62.4billion
3. Warren Buffett, Berkshire Hathaway – $43.8billion
4. Ingvar Kamprad, IKEA -$42.5billion
5. Bernard Arnault, Louis Vuitton – $42.3billion
6. Amancio Gaona, Inditex Group (Zara, Massimo Dutti and Oysho) – $38.8billion
7. Lawrence Joseph Ellison, Oracle Corp. – $38billion
8. Charles Koch, Koch Industries – $34billion
9. David Koch, Koch Industries – $34billion
10. Eike Batista, EBX Group – $29.8billion
11. Mukesh Ambani, Reliance Industries – $26.8billion
12. Li Ka-Shing, Cheung Kong Holdings, Hutchison Whampoa and Li Ka Shing Foundation – $25.8billion
13. Sheldon Adelson, Las Vegas Sands – $25.7billion
14. Christy Walton, Wal-Mart – $24.9billion
15. Stefan Persson, Hennes & Mauritz – $24.5billion
16. Lakshmi Mittal, ArcelorMittal – $23.6billion
17. Jim Walton, Wal-Mart – $23.4billion
18. Samuel Walton, Wal-Mart – $22.9billion
19. David Thomson, Thomson Reuters – $22.7billion
20. Liliane Bettencourt, L’Oréal – $22.4billion