With 1.7 million people waving signs, pennants and brooms lining the streets on a gloriously sunny day yesterday, the Philadelphia 76ers shared the NBA championship with their fans.

The parade began in the downtown area and proceeded about five miles down Broad Street to Veterans Stadium, where a crowd of 62,000 welcomed the team.

The parade snaked through crowds that were 10 and 15 deep in most areas, as confetti, torn telephone books and ticker tape cascaded through the windows of buildings as the 76ers passed.

"This is the biggest crowd I've ever seen in Philadelphia watching a parade," said Police Inspector Bernard Small.

As the team passed, many yelled "Sweep, Sweep, Sweep" or "We're No. 1," while Coach Billy Cunningham and owner Harold Katz balanced the NBA championship trophy on the front railing of the flatbed truck they rode.

Julius Erving and Andrew Toney were so taken by the celebrating that they began an impromptu dance as their car wheeled around inside the Vet.

"We thank you fans from the bottom of our hearts for this day and coming out here and sharing this with us," said Erving, who received the loudest and longest ovation. "There was nothing pretty about what we did to the NBA this year. It was absolutely beautiful" . . .

A group of Connecticut businessmen has reportedly made the Boston Celtics an offer to guarantee more than 10,000 season ticket sales if they played half their home games at the Hartford Civic Center, according to the Boston Globe.