24

there are only 24 hours in a day

Said when one is being asked to accomplish more than is possible within the span of a single day. I get that you want to clean out the garage, bake cupcakes, and go to the mall, but there are only 24 hours in a day. Why don't we spread these activities out over a few days, huh? Dude, there are only 24 hours in a day. There's no way we'll make it all the way to Cleveland tonight!
See also: 24, hour, there

twenty-four seven

All day, every day. Short for "twenty-four hours a day, seven days a week." Another hyphen can be used between "four" and "seven" if used as a modifier before a noun. Often written as 24/7. You know you can call me twenty-four seven if you ever need anything, OK? It's the only shop in the entire city that's open 24/7. We offer twenty-four-seven customer support for anyone whose credit card is lost, stolen, or locked.
See also: seven
Farlex Dictionary of Idioms.

twenty-four seven

all the time; twenty-four hours a day, seven days a week.
The phrase, which originated in the US, is often written 24/7 .
See also: seven
Farlex Partner Idioms Dictionary

twenty-four, seven

and 24-7
mod. all the time, twenty-four hours a day, seven days a week. He’s always at home, 24-7!
See also: seven

24-7

verb
See twenty-four, seven
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • there are only 24 hours in a day
  • bake up a storm
  • bake
  • bake up
  • a committee is a group of men who keep minutes and waste hours
  • group
  • get (something) over with
  • get it over with
  • try (something) out on (one)
  • try out on