The owners of 20,898 buildings owe New York City more than $555 million in back taxes, emergency repairs and water bills, according to the Department of Finance.

While the dollar figure enough to pay for pre-K, Mayor de Blasio’s pet project, it is actually 24 percent lower than in May 2013, according to the 60-day lien sale list released by city department to The Post.

The number of buildings 60 days or more behind on the tax and repair bills fell by 10 percent, the list showed.

The decline in the number of buildings in arrears and the amount owed to the city, experts said, is the result of the current feeding frenzy by the real estate industry to buy and redevelop properties.

That business activity is bringing fresh capital and investment to areas where previous owners were unable to keep up with debts and repairs on aging stock, the experts said.

The real amount owed to the city could be higher. The city typically culls properties with high lien-to-value ratios, or other issues, such as government-owned land, before producing the list.

This year, Brooklyn topped the list with 8,782 properties owing $212.8 million. The largest delinquent amount in the city is owed by a Brooklyn day care center of just 24,000 square feet.

That building, at 5 Quincy St., listed on city records as 26 Lexington Ave. and owned by Friends of Day Care Centers, Inc., has not paid a dime to the city in taxes or water bills since 1994.

It owes $9,908,086, including interest and other charges, according to the list.

The executive director did not return a call for comment.