db.x2iedn.xlarge is an Amazon Neptune size with 4 vCPUs, 128 GiB memory (Intel Xeon Family). In US East (N. Virginia) it costs $2.26 per hour on demand ($1,649.80 per month) for Standard storage. It is sold in 9 regions.
Prices by region
USD per hour, Standard storage. Reserved prices are no upfront, standard. Cheapest on-demand first.