Here's what I am hoping to accomplish

In the following columns:
D2
E2
G2
I2
J2
K2
L2
M2
N2
O2
P2

and in any cells below those, if there is a number in that cell, take that number:

- Divide it by 86400
- Change the formatting to Time HH:MM:SS

Any thoughts on how to achieve that?