Having finished a dismal ninth last season under Andrea Stramaccioni, Inter currently occupy the second Europa League qualifying place as they lie fifth in the table.
They trail leaders Juventus by 15 points but Napoli, in the third Champions League spot, by only five and veteran Javier Zanetti earlier told Gazzetta dello Sport that catching the latter and rejoining Europe's elite was a realistic aim.
"Yes, because the league is balanced," said the Argentinian. "At Napoli I did not see a big difference between the two teams."
Mazzarri told Sky Italia: "It has been excellent.
"Looking at the standings, we could have had four or five more points for what we have expressed on the field.
"There has been more here to give me grey hair than in other teams I have been at but I am lucky to be here.
"Inter is a club every club dreams about but I arrived at a particular time in the history of the club. I would have loved to come in to a different situation but I have shown I can take on any challenge.
"I have always had to work hard for everything, I have never had it easy but I am very pleased and satisfied with what I have achieved in my life."