Declension table of ?devyāyatana

Neuter	Singular	Dual	Plural
Nominative	devyāyatanam	devyāyatane	devyāyatanāni
Vocative	devyāyatana	devyāyatane	devyāyatanāni
Accusative	devyāyatanam	devyāyatane	devyāyatanāni
Instrumental	devyāyatanena	devyāyatanābhyām	devyāyatanaiḥ
Dative	devyāyatanāya	devyāyatanābhyām	devyāyatanebhyaḥ
Ablative	devyāyatanāt	devyāyatanābhyām	devyāyatanebhyaḥ
Genitive	devyāyatanasya	devyāyatanayoḥ	devyāyatanānām
Locative	devyāyatane	devyāyatanayoḥ	devyāyataneṣu

Compound devyāyatana -

Adverb -devyāyatanam -devyāyatanāt