Ella Henderson's 'Ghost' is officially the biggest song of the summer after shifting an incredible 578,000 copies between June and August. The former X-Factor contestant notched up her first No.1 with the catchy pop tune and we should expect the song to hover in the Top 40 for the next couple of months, given its prominent use on the new season the singing show.

Ella HendersonElla Henderson's 'Ghost' was a massive hit

Ella told Official Charts: "I am completely overwhelmed by the success of Ghost! To have one of the biggest selling songs of the year is absolutely insane. It doesn't feel real. I can't thank everyone enough for all the support. Thank you!"

Ghost, co-written with OneRepublic's Ryan Tedder - the man behind 'Bleeding Love' and 'Halo' - topped the Official Singles Chart in June after Ella's involvement in the 2012 series.

Simon Cowell was not on the panel during that series, but Henderson said she met him in a boardroom soon after.

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"I don't know what I was expecting," she told the Independent, "but it was such a chilled conversation, and he is just a normal guy. It was humbling to sit in a room with him, and talk on the same level. He said he wanted ours to be a long-term deal, and for me to take as long as I liked. He's been so encouraging all the way through."

Henderson also spoke of keeping grounded despite her immense popularity. 

"I don't expect anything from all this, you know," she said, "I just see it as a head start, and I'm lucky to have had it. I'm exactly where I want to be now, and I'll work hard to stay here."

Ella Henderson's new single, 'Glow', is out on 14 September. The album Chapter One is released on 22 September.