Paris and several hundred guests packed the Pier Friday night. The festivities fired up at around 8 PM, and lots of famous friends were on hand, including Demi Lovato, Lele Pons, Lance Bass and Diplo handled the DJing. Of course, her fam was front and center -- Kathy and Nicky especially made the rounds.

Paris was having a great time, taking photos with lots of people and, of course, mugging all the way!

This party was strictly fun ... with a roller coaster, a ferris wheel and bumper cars at the ready, and everyone took advantage.

There were also the standard Santa Monica Pier games, including Wack-o-mole, balloon popping, a mini basketball game, ring tosses, and on and on. Partygoers who were good enough won stuffed animals.

There were the obligatory street performers on stilts with twirling lighted umbrellas.

Paris, ever the entrepreneur, gave out boxes of her perfume -- Rush and Electrify.

And, this is the best ... plastered above the sink -- "#Forever Hilton Reum, That's Hot, Sliving."

As we reported, Paris tied the knot Thursday with Carter in an opulent ceremony at her grandpa's former estate. Lots of famous folks showed, including Kim Kardashian, Nicole Richie, Demi Lovato, Paula Abdul, Kyle Richards, Bebe Rexha, Emma Roberts and Evan Ross.

Gotta say ... one of the more spectacular celeb weddings, and it's not over. There's a super formal, black-tie shindig back at grandpa's estate Saturday night. We'll have pics Sunday, so stay tuned.

And, in case you didn't see ... check out the tent in the backyard. It's insanely huge.