וַיִּסְע֧וּ בְנֵֽי־יִשְׂרָאֵ֛ל מֵרַעְמְסֵ֖ס סֻכֹּ֑תָה כְּשֵׁשׁ־מֵא֨וֹת אֶ֧לֶף רַגְלִ֛י הַגְּבָרִ֖ים לְבַ֥ד מִטָּֽף׃
And the children of Israel journeyed from Rameses to Succoth, about six hundred thousand men on foot, beside children.
Read kabbalistic (mystical) interpretation of Exodus 12:37: and classical mystical sources.