The total number of Bitcoin nodes around the globe is constantly growing and as of July 2019, there were over 10,000 reachable nodes according to Bitnodes.io. Nodes are required to keep the Bitcoin network secure as well as decentralized.
In order for a node to be considered active, it must have the most up-to-date copy of the blockchain and relay information about new blocks and transactions to other nodes. The more active nodes there are, the more secure and decentralized the network becomes.
The vast majority of nodes are located in North America (42%), Europe (30%), and Asia (19%). This is not surprising given that these are also the continents with the highest concentration of Internet users.
However, it is important to note that anyone can run a Bitcoin node from anywhere in the world regardless of their location.
Running a Bitcoin node requires a fair amount of technical know-how and can be quite expensive due to the high amount of electricity needed to power them. For this reason, most nodes are run by large organizations such as exchanges, wallets, or payment processors who can afford the costs associated with running them.
Individual node operators also tend to be quite passionate about Bitcoin and believe in its long-term success.
Despite the challenges associated with running a node, the number of active nodes continues to grow year after year which is a positive sign for the future of Bitcoin. As more people become aware of Bitcoin and its benefits, we can expect the number of nodes to continue to increase which will only make the network stronger.