What is the smallest rank number of those used to rank the islands? 
CREATE TABLE table_13897690_1 (rank INTEGER)
SELECT MIN(rank) FROM table_13897690_1
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_13897690_1 (rank INTEGER) Question: What is the smallest rank number of those used to rank the islands?  [/INST] SELECT MIN(rank) FROM table_13897690_1 </s>