Carey described Packer's proposal, which took place in her New York hometown on Jan. 21 as "very romantic," and couldn't help but marvel over the epic 35-carat diamond ring that the Australian billionaire gave her when he popped the question.
"It's so heavy I can't lift my arm up!" she joked. "It's a nice chunk."
The singer also gushed about her husband-to-be, whom she describes as "generous" and "good-hearted."
"He's an exceptional person and really...it gets more romantic by the day, so it's very sweet," she said of Packer, 48. "He's young at heart, but also serious. And I mean that in the best way."
So, when will the couple be walking down the aisle?
"If everything works out, it will be somewhat soon," Carey laughed, adding that there's a lot of planning to be done, even though the couple plans to keep the wedding somewhat intimate. "We are not doing a big wedding because he did two big weddings, and it's kind of like, 'I've done a big wedding [too]'... We would rather make it beautiful but humble."
"I am very excited about the dress, but I don't want to talk about it yet, as I have to have my first fitting," she added.
It will be the third marriage for Packer, who has three children from his marriage to Australian model and singer Erica Baxter. Carey was married to actor and comedian Nick Cannon from 2008-2014, with whom she shares 4-year-old fraternal twins, Monroe and Moroccan.
Mariah Carey opens up about engagement to James Packer: 'He's an exceptional person'
Nikki Reed and Ian Somerhalder
The cute couple gave everyone major wedding envy when they tied the knot in a fairytale Malibu wedding in April. Reed stunned in a lace gown while Somerhalder opted for an off-white suite. And if their social media posts are any indication, the post-wedding bliss is still alive and well months after the big day!
(Photo by Pascal Le Segretain/Getty Images)
David Arquette and Christina McLarty
Arquette and McLarty were all smiles on their wedding day in April as they said "I do" in front of their closest family and friends. They were joined at the ceremony by their 1-year-old son, Arquette's daughter and their two basset hounds. And we have to admit, their official wedding photo may be the cutest thing you'll see all day!
(Photo by David S. Holloway/David Arquette and Christina McLarty via Getty Images)
Benji Madden and Cameron Diaz
The pair started 2015 off with a bang after getting married in January. They tied the knot at the actresses' luxe Beverly Hills home in an intimate ceremony. Of course, some of Diaz's bridesmaids included famous gal pals such as Nicole Richie and Drew Barrymore.
(Photo by Noel Vasquez/GC Images)
Gabrielle Union and Dwyane Wade
The "Being Mary Jane" actress and NBA star gave us all major #WeddingGoals with a sophisticated ceremony that's seriously straight out of a movie. The star-studded bash included John Legend as the musical performer, so it was definitely a night to remember.
Johnny Depp and Amber Heard
The "Pirates of the Caribbean" star and sexy actress said "I do" this past February not once, but twice! The couple tied the knot at Depp's home in the U.S. before jet-setting to his private island in the Bahamas.
(Photo by Jason Merritt/Getty Images)
Desiree Hartsock and Chris Siegfried
It was a happy ending for 'The Bachelorette' star when she tied the knot with Siegfried in January after a whirlwind 20-month romance! While their oceanside wedding was straight out of a fairytale, Hartsock had one request -- "No red roses!"
(Photo by Tom Briglia/Getty Images)
Sofia Vergara and Joe Manganiello
The sexy couple said '"I do" in a lavish Miami ceremony in November. Vergara donned a gorgeous, custom-made Zuhair Murad gown as her 22-year-old son walked her down the aisle. It's pretty clear duo wasn't shy about sharing their wedding bliss with all the photos they posted on Instagram -- and we don't blame them!
Benedict Cumberbatch and Sophie Hunter
The duo exchanged vows on Valentine's Day in a tasteful affair at a medieval church that dates back to the 12th century. Between the incredible location and Hunter's gorgeous, one-of-a-kind Valentino dress, we were totally getting "Downton Abbey" vibes.
(Photo credit should read Anthony Devlin/AFP/Getty Images)
Whitney Eve Port and Tim Rosenman
The former "The Hills" star wanted to make her walk down the aisle a memorable one with a leggy number that's far from traditional! And we have to admit, the 30-year-old definitely turned up the heat in Palm Springs with her sexy look.
Chad Michael Murray and Sarah Roemer
Talk about a double delight! The actor secretly married his "Chosen" co-star in June while also dropping big baby news. This isn't Murray's first marriage -- he got hitched to "One Tree Hill" co-star Sophia Bush in 2005.
(Photo by Nick Smith/BuzzFoto via Getty Images)
Ashton Kutcher and Mila Kunis
The very private pair kept their July 4th wedding under wraps just like their engagement last year. The former "That 70s Show" co-stars tied the knot in a secluded garden that definitely made us all go green with envy!
(Photo by Justin K. Aller/Getty Images)
Mary-Kate Olsen and Olivier Sarkozy
The duo's secret wedding in early December was definitely a smokey affair! The Olsen twin and French businessman (who's 17 years her senior) had a lavish reception with 50 of their closest friends and family and tables filled with bowls of cigarettes.
(Photo by Monica Schipper/Getty Images)
Jenni "JWOWW" Farley and Roger Mathews
The former "Jersey Shore" didn't hold back with pulling off her dream wedding to her hubby just five years after they met and fell in love at the shore! The bride wore two dresses for the occasion, including one that had a 10-foot train. And of course, in typical JWOWW fashion she also revealed that she's expecting Baby No. 2!
Rob Dyrdek and Bryiana Noelle
The couple shared snaps of the stunning affair in September on Instagram -- and we've never seen a couple more in love! The MTV star proposed to his ladylove at Disneyland in April and by the looks of the photos they posted this time around, the wedding was just as over-the-top.
Billy Joel and Alexis Roderick
The pair, who had been together since 2009, tied the knot at a surprise wedding on the Fourth of July at their estate in Long Island. Guests thought they were just attending the couple's annual Independence Day party, but that was clearly not the case! The magical affair, which was held at Joel's estate on Long Island, was presided over by his long time friend New York Governor Andrew Cuomo
(Photo by Myrna Suarez/WireImage)
Bar Refaeli and Adi Ezra
The Sports Illustrated model tied the knot late September to Ezra, who she called her "best friend" in this adorable Instagram snap! Refaeli donned a breathtaking lace Chloe gown for big day and the groom looked just as handsome standing next to her in a black-and-white ensemble.
Nicky Hilton and James Rothschild
The heiress married Rothschild in a luxe ceremony fit for a King and Queen -- literally! The duo made their love official in a breathtaking event at Kensington Palace in London. Hilton wore a stunning Valentino number while toting a white bouquet and long train.