I have actually never heard anyone say it this way specifically where I grew up… so technically the answer is “no”?

I tried to dug around and found a Reddit post saying this:

“The Oxford English Dictionary (OED) defines the term as “twenty-four hours a day, seven days a week; constantly”. It lists its first reference to 24/7 to be from a 1983 story in the US magazine Sports Illustrated in which Louisiana State University player Jerry Reynolds describes his jump shot in just such a way: 24-7-365.”

So this might be a fairly new idiom? Which would explain why it’s not really a thing in a lot of cultures… but I assume they have their ways of referring to this.

number of hours and days are the same

Ok akktually Japan has a rather interesting 30-hour day thing in the context of businesses… but jokes aside, the 24-hour, 7-day week system is indeed quite universal