Adverb
24 hours per day, seven days per week. Designates a round-the-clock service, typically including holidays, as might be offered by a supermarket, ATM, gas station, concierge service or manned data center.
They're open twenty-four seven; you can go there any time you want.
(colloquial) Constantly, without interruption.
Source: en.wiktionary.orgtwenty-four-seven
One of the big misconceptions about me is that I walk around in mini-skirts and high heels twenty-four seven and go to the gym in heels. Carmen Electra