Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_3637 ( "No" real, "Origin City (Country)" text, "Destination City (Country)" text, "Train Name No" text, "Operator Name" text, "Distance" text, "No. of Stops" text, "Frequency" text, "Scheduled running time" text )

### Question ###
what is the no when the distance is 4168km?

### Accurate SQL ###

SELECT "No" FROM table_3637 WHERE "Distance" = '4168km'