The actual Social Security benefits cannot be divided. This is because the Social Security benefits are regulated by the federal government and there is really no way to divide them and effectuate that through those regulations. However, this does not mean that a former spouse is not entitled to a portion of their spouse's Social Security benefit, including survivor benefits. As long as they have been married for at least 10 years, their work credits do not exceed half of their spouse's, and they do not remarry, they may qualify for these benefits.
This makes it an important consideration if you are in the process of divorce and you are approaching your 10-year marriage date. It may be beneficial to delay the divorce a little bit. Once you pass that 10-year mark you're entitled to these benefits and there's really no negative effect to your spouse in doing so.