Quran clearly mention that Allah is Eternal and not Immortal.

Immortal means who is born or created or has beginning but no ending. But Allah is not born and will never die; Allah is Eternal...

Say: He is Allah, the One and Only;

Allah, the Eternal, Absolute;

He begetteth not, nor is He begotten;

And there is none like unto Him.

(Quran: 112: 1-4)

 In above verses it is clearly mentioned Allah is ETERNAL and not Immortal, Allah has no creator or parents and has no partner or wife or children. And there is none like unto Him and HE cannot be compared to any creations.