Question: What is the port number of the SMTP

Answer:

The port number commonly used for the Simple Mail Transfer Protocol (SMTP) is port 25. This port is used for outgoing mail transfer from an email client or mail server to the recipient's mail server. However, it's worth noting that port 25 is often blocked or restricted by internet service providers (ISPs) to prevent spam and abuse. As an alternative, the use of port 587 (submission) or port 465 (SMTPS) with SSL/TLS encryption is recommended for secure and authenticated email communication.