Barcelona announced on Thursday afternoon that Coutinho would wear the jersey No. 7 for the new season. 
The No. 7 jersey was most recently held by Arda Turan, in the past, it has famously been worn by the likes of Pedro Rodriguez, Luis Figo, Pep Guardiola and David Villa.

It's also been reported recently that Barcelona are still trying to get a Portuguese passport for Coutinho in an attempt to free up a third non-European Union playing spot in their squad, according to ESPN FC.
Brazil's Coutinho currently fills one of the three (3) spots but the player is eligible to be approved for a Portuguese passport Portuguese passport with the help of his wife, Aine.

Barcelona hope to get this sorted before the match of the Supercopa de Espana  with Sevilla on Sunday because La Liga only allows three non-EU players in any matchday.
Barcelona are likely to sell the likes of Yerry Mina and Marlon Santos, whom currently occupy the two other non-EU spots, in the few days while Barcelona hopes to have Malcolm, Arturo Vidal and Arthur Melo occupy the spots, pending the decision made on Coutinho.