Strong's numbers

קֹהֶלֶת H6953

qôheleth

ko-heh'-leth

feminine of active participle from קָהַל; a (female) assembler (i.e. lecturer); abstractly, preaching (used as a 'nom de plume', Koheleth); preacher.

קֹהֶ֫לֶת, (קוֹהֶ֫לֶת) n.m. collector (of sentences), or (AV RV) preacher

From Brown, Driver, and Briggs, A Hebrew and English Lexicon of the Old Testament (1906), in the public domain.

Shown in the King James Version (KJV), whichever translation you read in — it is the text these numbers are tagged against.

Ecclesiastes 1:1
The words of the Preacher, the son of David, king in Jerusalem.
Ecclesiastes 1:2
Vanity of vanities, saith the Preacher, vanity of vanities; all is vanity.
Ecclesiastes 1:12
I the Preacher was king over Israel in Jerusalem.
Ecclesiastes 7:27
Behold, this have I found, saith the preacher, counting one by one, to find out the account:
Ecclesiastes 12:8
Vanity of vanities, saith the preacher; all is vanity.
Ecclesiastes 12:9
And moreover, because the preacher was wise, he still taught the people knowledge; yea, he gave good heed, and sought out, and set in order many proverbs.
Ecclesiastes 12:10
The preacher sought to find out acceptable words: and that which was written was upright, even words of truth.