Where immovables of an estate are encumbered by annuities by special mortgage, each of the co-heirs may demand that the annuities be repaid and the immovables made free before the lots are formed. If the co-heirs share the estate in the state it is in, the encumbered immovable must be valued at the same rate as the other immovables; the capital of the annuity is deducted from the total price; the heir into whose lot this immovable falls remains solely responsible for servicing the annuity and must guarantee his co-heirs.