פְּקֻדֵיהֶ֖ם לְמַטֵּ֣ה יִשָּׂשכָ֑ר אַרְבָּעָ֧ה וַחֲמִשִּׁ֛ים אֶ֖לֶף וְאַרְבַּ֥ע מֵאֽוֹת׃ (פ)
those that were numbered of them, of the tribe of Issachar, were fifty and four thousand and four hundred.
Read kabbalistic (mystical) interpretation of Numbers 1:29: and classical mystical sources.