SB 12.13.3

purāṇa-saṅkhyā-sambhūtim
 asya vācya-prayojane
dānaṁ dānasya māhātmyaṁ
 pāṭhādeś ca nibodhata
Synonyms: 
purāṇa — of the Purāṇas; saṅkhyā — of the counting (of verses); sambhūtim — the summation; asya — of this Bhāgavatam; vācya — the subject matter; prayojane — and the purpose; dānam — the method of giving as a gift; dānasya — of such gift-giving; māhātmyam — the glories; pāṭha-ādeḥ — of teaching and so on; ca — and; nibodhata — please hear.
Translation: 
Now please hear a summation of the verse length of each of the Purāṇas. Then hear of the prime subject and purpose of this Bhāgavata Purāṇa, the proper method of giving it as a gift, the glories of such gift-giving, and finally the glories of hearing and chanting this literature.
Purport: 

Śrīmad-Bhāgavatam is the best of all Purāṇas. Śrīla Viśvanātha Cakravartī Ṭhākura explains that the other Purāṇas will now be mentioned just as the assistants of a king are mentioned in connection with his glorification.