18556

18556 is a number that falls between 18555 and 18557 in the sequence of natural numbers. It is an even number, as it is divisible by 2 without leaving a remainder. In base 10, it is written as "eighteen thousand five hundred fifty-six." In scientific notation, it is expressed as 1.8556 x 10^4.

The number 18556 is significant in various contexts. In mathematics, it is a composite number, meaning it has factors other than 1 and itself. Its prime factorization is 2^2 x 3 x 2597. In computer science, 18556 is used as a port number in the Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) for various applications, including the Microsoft SQL Server Database Mail feature.

In popular culture, 18556 is referenced in the video game "Half-Life 2," where it is the code for the combination lock on the door leading to the Citadel. Additionally, it is mentioned in the novel "The Da Vinci Code" by Dan Brown, where it is part of a sequence of numbers that lead to the discovery of a hidden message.

Overall, 18556 is a number with diverse applications and references in various fields. Its properties and significance make it an interesting subject for further exploration and study.