Other’s and others’ are both correct forms of the word “other.” Use others when referring to a group of people or things, such as “The others are waiting for you outside.” Use others’ for plural possessive form, such as “The others’ opinions are very important to me.” Other’s acts as the singular possessive form.

It’s correct to use “others” as the plural and “other’s” to talk about the singular possessive. You can use “others’” as a plural possessive, but it’s much more likely that you’ll require a secondary noun for this to make sense (i.e. “other people’s”).