Yes, a.echegaray.org can receive emails.
Yes, a.echegaray.org seems to be a legitimate domain.
A record
86.109.177.94
MX records
alt1.aspmx.l.google.com
64.233.186.26
alt2.aspmx.l.google.com
209.85.202.27
alt3.aspmx.l.google.com
142.250.13.26
alt4.aspmx.l.google.com
172.217.218.27
aspmx.l.google.com
209.85.232.27