Who knows one hundred thirty-one?
Please cite/link your sources, if possible. At some point at least twenty-four hours from now, I will:
Upvote all interesting answers.
Accept the best answer.
Go on to the next number.
The first and last letters of the first four chapters of Tehillim add up to 131, which is also the numerical value of סמאל (the angel of evil). We therefore say these four chapters on Yom Kippur night, so that G-d save us from inadvertent uncleanness on this holy day.
(Pri Eitz Chaim, Yom Hakippurim 2)
Various later commentators point out that the sum of the relevant letters is actually only 126. Possible answers include:
According to Sharon Chisvin, 131 young Holocaust orphans were absorbed by Winnipeg after the war.