changing datagridview header text

Question

hey guys i have a class that i defined variables like that
 
public string cekilis_no{ get; set; }
public string cekilis_tarihi { get; set; }
public string sayi_bir { get; set; }
public string n_iki { get; set; }
public string n_uc { get; set; }
public string n_dort { get; set; }
public string n_bes { get; set; }
public string n_alti { get; set; }
and i give their values with the datas from my database with SqlDataReader and i show them by datagridview in my form..but my problem is that the headers shown as i wrote in my class like n_bes,n_alti, like here..how i can show it like Number 5 or Number 6 ??