Thanks @nivrig for sharing.
I’ve now put to 0 following which I didn’t do earlier:
CC_ENABLE_SCRIPT_BINDING
CC_USE_JPEG
CC_USE_TIFF
CC_USE_WEBP
CC_USE_NAVMESH
My new debug.apk size reduced from 10MB to 9.7MB 
Can you please tell what’s this arm64? 
I mean, do I need to this for android devices, or just arm-v7a is enough!
I am building just for armeabi-v7a for android.