You provisioned Partner Interconnect and must create a Cloud Router and VLAN attachment. Which Autonomous System Number (ASN) should you assign to the Cloud Router for this setup?

When configuring a Cloud Router for Partner Interconnect, you must use the Google-provided public ASN 16550. This is a specific requirement for Partner Interconnect to establish the BGP session with the partner's network. Using a 2-byte private ASN (64512-65535) or a 4-byte private ASN (4200000000-4294967294) is appropriate for Cloud VPN or Dedicated Interconnect, or when peering with your own on-premises router directly, but not for Partner Interconnect where Google acts as the peering entity with the partner. Google's public ASN 15169 is used for Google's global network peering, not for Cloud Router configurations in Partner Interconnect.