4561

4561 is a natural number that follows 4560 and precedes 4562. In mathematics, it is a prime number, meaning it has only two distinct positive divisors: 1 and itself. It is also an odd number and is congruent to 1 modulo 4.

In decimal notation its digits are 4, 5, 6, and 1. The sum of the digits is 16, giving a digital root of 7. These digit properties are often used in basic arithmetic checks and quick mental math, though they do not determine primality.

Outside pure mathematics, 4561 is used as an identifier in various systems. It may appear as a postal code, a catalog or part number, a model designation, or an internal reference within different organizations. The specific meaning depends on the coding scheme or context in which it is employed.

In number theory, primes such as 4561 are studied for properties related to primality testing, factorization, and modular arithmetic. As a small prime, it can serve as a simple example in introductory material on topics such as divisibility, modular congruences, and prime-based algorithms. While the number itself has no universal significance beyond mathematics, its status as a prime gives it relevance in theoretical discussions and practical demonstrations.