The iHeartRadio Music Awards are about to start in Los Angeles and some of the biggest names in music and reality TV are arriving … and we’ve got all the photos.

Kelsea Ballerini, Jojo Siwa and Benson Boone are some of the first arrivals … and they are all looking super fashionable … with Jojo really making a statement.

LL Cool J is tonight’s host at Hollywood’s Dolby Theater … and GloRilla is among the performers. She showed up in a skintight, black dress and blonde hair.

Music is the reason for the occasion, but this is Hollywood and reality TV is not to be ignored … so “Vanderpump Rules” stars Ariana Madix and Brittany Cartwright are among the celeb guests in attendance.

Jenny McCarthy is in the house too … and like a fine wine she just keeps getting better with age.

Green Day is nominated for three awards … Alternative Artist of the Year, Rock Artist of the Year and Alternative Song of the Year for “Dilemma” … and they look ready for an acceptance speech … we’ll see if they win.