The integer converted from decimal to hexadecimal is "divide by 16 and take the remainder in reverse order",

For example, 500

500/16 = 31... 4 ( In reverse order, this is the highest bit)

31 /16 = 1 …… 15 (15 is F in hexadecimal)

1 /16 = 0 …… 1

So it is 1F4.