2543

2543 is a natural number that comes after 2542 and before 2544. In mathematics, 2543 is a prime number, meaning it has exactly two distinct positive divisors: 1 and itself. It is an odd number and is congruent to 3 modulo 4, and as a consequence it cannot be expressed as a sum of two squares. Its prime status implies that its only divisors are 1 and 2543. The digital root of 2543 is 5 (2 + 5 + 4 + 3 = 14; 1 + 4 = 5). In Roman numerals, 2543 is written as MMDXLIII.

In calendrical and broader numeric contexts, 2543 can designate a year in the Gregorian calendar (2543 CE), a future time point used in discussions of history, fiction, or planning. Beyond dating, 2543 may appear as an identifying number or catalog entry in various systems that assign sequential numbers to objects, documents, or components. As with many integers, its primary significance lies in its mathematical properties, with only one positive unit factor aside from 1 and itself, and in its use as a label within different numbering schemes.