וְלָקַחְתָּ֗ חֲמֵ֧שֶׁת חֲמֵ֛שֶׁת שְׁקָלִ֖ים לַגֻּלְגֹּ֑לֶת בְּשֶׁ֤קֶל הַקֹּ֙דֶשׁ֙ תִּקָּ֔ח עֶשְׂרִ֥ים גֵּרָ֖ה הַשָּֽׁקֶל׃
thou shalt take five shekels apiece by the poll; after the shekel of the sanctuary shalt thou take them—the shekel is twenty gerahs.
Read kabbalistic (mystical) interpretation of Numbers 3:47: and classical mystical sources.