Yes, ymail4.com can receive emails.
No, ymail4.com is a throwaway domain and should be blocked.
You can use MailCheck's free API to automatically block throwaway emails. Read our documentation to get started. No registration required.
A record
104.27.169.101
MX records
mxa.mailgun.org
18.205.100.2
mxb.mailgun.org
52.25.162.252