Is there a minimum number of people to buy social security?

Is there a minimum number of people to buy social security? If there are 3-4 people in the company, they should all pay social security.

Paying social insurance is legal and compulsory, and there is no question of the proportion of paying social insurance. It is illegal to conceal. As employees of enterprises, they should safeguard the legitimate rights and interests of employees according to law, instead of thinking about paying less or not paying social insurance for employees. Once employees know, they will inevitably report or apply for labor arbitration, and the result will inevitably be to pay social insurance for employees and be punished.