362560 is the number of days since Jan. 1, 1900
.304548611111111 is the decimal portion of one day that 7:18:33 is.
Strictly speaking:
36256 is the number of days since Jan 1, 1900,
and
0.30454861111111 is time value.
You might find these instructive:
=A1&""
=A2&""
Excel is using the "underlying" numeric time value in the concatenation (as in the link). If you did want text, then:
=Text(A1,"m/d/yyyy")&" "&Text(A2,"hh:nn:ss")
Also, Excel uses some funny dates for the first two months of the year 1900 due to an error in the leap year calculations - so Excel actually starts out a "day behind" so to speak, and is back in order on March 1, 1900. This bug was actually originally in Lotus 1,2,3 but was kept in Excel for compatibility (back in the day, Lotus was used a lot in spreadsheet software).