Please try with the below code snippet.
@Html.RadioButtonFor(model => model.StatusId, "2", Model.StatusId == '2' ? new {@Checked = "checked"} : '')
OR
@Html.RadioButtonFor(model => model.StatusId, "2", Model.StatusId == '2' ? new {@Checked = "checked"} : null)
If above code is not worked then please provide your rendered html code of this radiobutton/input.