Wiktionary
twenty-four seven
adv. 1 24-hours per day, 7-days per week. A round-the-clock service, typically including holidays, as might be offered by a supermarket, ATM, gas station, concierge service or manned data center. 2 (context colloquial English) Constantly, without interruption.
Usage examples of "twenty-four seven".
I brought Keck over from the Agency, spent twenty-four seven with him until he was up to speed.