The administrator, if there be sufficient assets, shall redeem all property of the deceased under mortgage, pledge or levy of execution for less than its value, or which if unredeemed would diminish the value of the estate, unless he shall by license sell it subject to the encumbrance; and neglect so to redeem shall be deemed maladministration and waste. Provided however, when real estate under mortgage is specifically devised, the devisee shall take such real estate subject to the mortgage, unless the testator in his will or by insurance has provided expressly or by necessary implication that such mortgage be otherwise paid; and if the note or obligation of the testator secured by such mortgage be paid out of other property in his estate after his decease, the executor of his will, at the request of any person interested, and by leave of the probate court shall sell such specifically devised real estate for the purpose of satisfying the estate of the testator for the amount so paid, together with the costs and expenses thereof.