how to max data type varchar value in sql server

Question

 

  In database design as follows (table name company)

Fieldname                                   Data Type
Compid (primary key)                  char(10)

In database record as follows (table name company)
Compid
1
2
3
4
5

i want to get max value of compid in company table.
for that how can i write the sql query.