Write the following in Roman numerals.
$25819$

Hint: In order to solve this question first we will write the basic conversion of roman numerals further we will discuss the procedure to convert a number in the form of roman numerals.

Complete step-by-step answer:
Given arabic number is $25819$

Roman numerals used to make the conversion:

\[\begin{array}{*{20}{l}}
  {I{\text{ }} = {\text{ }}1} \\
  {V{\text{ }} = {\text{ }}5} \\
  {X{\text{ }} = {\text{ }}10} \\
  {C{\text{ }} = {\text{ }}100} \\
  {D{\text{ }} = {\text{ }}500} \\
  {\left( V \right){\text{ }} = {\text{ }}5,000} \\
  {\left( X \right){\text{ }} = {\text{ }}10,000}
\end{array}\]
Now we will proceed further by discussing its procedure step by step

Step 1 - Break the number (decompose it) into place value subgroups:
\[25,819{\text{ }} = {\text{ }}20,000{\text{ }} + {\text{ }}5,000{\text{ }} + {\text{ }}800{\text{ }} + {\text{ }}10{\text{ }} + {\text{ }}9\]

Step 2- Convert each subgroup in their respective roman numerals:
\[20,000{\text{ }} = {\text{ }}10,000{\text{ }} + {\text{ }}10,000{\text{ }} = {\text{ }}\left( X \right){\text{ }} + {\text{ }}\left( X \right){\text{ }} = {\text{ }}\left( X \right)\left( X \right)\]
\[5,000{\text{ }} = {\text{ }}\left( V \right)\]
\[\begin{array}{*{20}{l}}
  {800{\text{ }} = {\text{ }}500{\text{ }} + {\text{ }}100{\text{ }} + {\text{ }}100{\text{ }} + {\text{ }}100{\text{ }} = {\text{ }}D{\text{ }} + {\text{ }}C{\text{ }} + {\text{ }}C{\text{ }} + {\text{ }}C{\text{ }} = {\text{ }}DCCC} \\
  {10{\text{ }} = {\text{ }}X} \\
  {9{\text{ }} = {\text{ }}10{\text{ }} - {\text{ }}1{\text{ }} = {\text{ }}X{\text{ }} - {\text{ }}I{\text{ }} = {\text{ }}IX}
\end{array}\]

Step 3- Wrap up the Roman numeral:
\[\begin{array}{*{20}{l}}
  {25,819{\text{ }} = {\text{ }}20,000{\text{ }} + {\text{ }}5,000{\text{ }} + {\text{ }}800{\text{ }} + {\text{ }}10{\text{ }} + {\text{ }}9{\text{ }} = } \\
  {\left( X \right)\left( X \right){\text{ }} + {\text{ }}\left( V \right){\text{ }} + {\text{ }}DCCC{\text{ }} + {\text{ }}X{\text{ }} + {\text{ }}IX{\text{ }} = } \\
  {\left( X \right)\left( X \right)\left( V \right)DCCCXIX}
\end{array}\]

Hence the required answer is \[\left( X \right)\left( X \right)\left( V \right)DCCCXIX.\]

Note- Roman numerals are a number system which originated in ancient Rome and remained the standard way of writing numerals well into the Late Middle Ages throughout Europe. Numbers within this scheme are represented by combinations of Latin alphabet letters. Just seven symbols are used by the Roman numeral system: \[I,{\text{ }}V,{\text{ }}X,{\text{ }}L,{\text{ }}C{\text{ }},{\text{ }}D,\] and $M$. $I$ reflect the number $1$, $V$ being \[{\mathbf{5}}\], $X$ being $10$, $L$ being $50$, $C$ being $100$, $D$ being $500$, and $M$ being $1000$.