Explanation

China has a 22,100-kilometer land border with 14 countries:

1. Afghanistan
2. Bhutan
3. India
4. Kazakhstan
5. North Korea
6. Kyrgyzstan,
7. Laos
8. Mongolia
9. Myanmar (Burma)
10. Nepal
11. Pakistan
12. Russia
13. Tajikistan
14. Vietnam

The longest borders are with Mongolia (4,677 km), Russia (3,645 km), India (3,380 km), and Myanmar (2,185 km).