The value of this property can be also obtained in the "PmaRoot" item of the INFO system (when looking into the object with this property). This property can be changed in the INFO system by clicking the "Actions" button. See "PmaRoot > Permissions > InfoEdit" permission.
var oNumber = pMe.Pm("/Number0");
var val = oNumber.Value; //Reading the value
oNumber.Value = val; //Writing the value