||According to the number of their names, the tally of all the first-born over one month old was 22,273.
Vayehi chol-bechor zachar bemispar shemot miben-chodesh vamalah lifkudeyhem shnayim ve'esrim elef shloshah veshiv'im umatayim.
||God spoke to Moses, saying:
Vayedaber Adonay el-Moshe lemor.
It is significant to note that the first-born comprised only one out of 27 Israelites. If the fact that they were numbered from only one month is taken into account, while the count of 603,550 is for those over 20 years old, it comes out that the first-born were approximately one out of 45. This may be because the Israelites had huge families in Egypt (see Rashi on Exodus 1:7). It is also possible that many first-born did not observe the first Passover and died in Egypt. Another possibility is that the first-born of many families were girls.