Declension table of ?gandharvatva

Neuter	Singular	Dual	Plural
Nominative	gandharvatvam	gandharvatve	gandharvatvāni
Vocative	gandharvatva	gandharvatve	gandharvatvāni
Accusative	gandharvatvam	gandharvatve	gandharvatvāni
Instrumental	gandharvatvena	gandharvatvābhyām	gandharvatvaiḥ
Dative	gandharvatvāya	gandharvatvābhyām	gandharvatvebhyaḥ
Ablative	gandharvatvāt	gandharvatvābhyām	gandharvatvebhyaḥ
Genitive	gandharvatvasya	gandharvatvayoḥ	gandharvatvānām
Locative	gandharvatve	gandharvatvayoḥ	gandharvatveṣu

Compound gandharvatva -

Adverb -gandharvatvam -gandharvatvāt