How to check if all elements of an array exists in a table?
I recommend to use the application code to insert the array into a Temporary table, including an identity field so you can store every record, even if it is repeated. (the syntaxis is the same as CREATE TABLE but using CREATE TEMPORARY TABLE):

CREATE TEMPORARY TABLE A (
     id BIGINT NOT NULL AUTO_INCREMENT,
     number BIGINT NOT NULL,
     PRIMARY KEY (id)
);


Then make a query to check/determine if the number exists in the large table. Something like this:

--supose the temporary Table is A and the big table is B and the fields you are comparing ara called NUMBER.

SELECT A.id, A.number as ARRAY_NUMBER,
CASE
    WHEN B.number IS NULL THEN 'not found'
    ELSE 'found'
END as FOUND_IN_TABLE
FROM A LETF OUTER JOIN B ON A.number = B.number


good luck!