25,589
Dividing by 5 aint hard. Just double it then divide it by 10
so
5432345678909876543211234567890 doubled is
10864681357819753086422469135780, so that divided by 10 is just
1086468135781975308642246913578
Now I did that in my head so I could be wrong

2
5-5 + 8 = 9