The number "5,678" is a whole number that comes after 5,677 and before 5,679. It is composed of four digits: 5, 6, 7, and 8. In the decimal system, it represents five thousand six hundred seventy-eight. In terms of place value, the digit "5" is in the thousands place, "6" is in the hundreds place, "7" is in the tens place, and "8" is in the ones place. This number can be used in various contexts, such as counting items, measuring distances, or representing data in statistics.