25190−8190 is divisible by 25−8=17; 19190−2190 is divisible by 19−2=17.
25190−19190 is divisible by 25−19=6; 8190−2190 is divisible by 8−2=6.
So the full expression is divisible by lcm(17,6)=102=17×6, and specifically by lcm(17,2)=34.
Divisible by 34 but not by 14