Can a property name and a method name be same in C#?

I have a class which contains a property:

public bool IsMandatory {get;set;}

Now I am adding a method IsMandatory(string str).

public bool IsMandatory(string str)
{
  //return false;
  //return true;
}

I am getting a compile time error that

the type already contains a definition for 'IsMandatory'

Can't a method name and property name be same in C# ? We use a method and property in different way, why is this giving compile error ?