 What is the first locomotive that has a SLM number lower than 924?
CREATE TABLE table_41775 (
    "Built" real,
    "Number" real,
    "Type" text,
    "SLM Number" real,
    "Wheel arrangement" text,
    "Location" text,
    "Notes" text
)
SELECT MIN("Number") FROM table_41775 WHERE "SLM Number" < '924'