There aren't even 100 000 Somalians living in Sweden, so it would be quite hard to deport 100 000 social welfare-Somalis. People born in Somalia is the 7th largest group of immigrants, and makes up for the largest group if we only look at African nations.

The real number is around half, 67000.

Now if we assume social welfare-Somalis is a derogatory generalization of all kind of immigrates, including non-Somalis, then it is likely to be more than 100 000 immigrants that is on social welfare. They just won't all be Somalis, or even be the majority of them.