Turn the year 1961 upside down and it looks the same. When was the last similar year before 1961?

问题描述:

Turn the year 1961 upside down and it looks the same. When was the last similar year before 1961?

问题是:
将1961年的数字倒过来,基本一样.前面还有一个和这个一样的年是哪一年?
答案是1691年,倒过来也是1691.