It's All About Meaning, Not Necessarily About the Length
The blog post dated March 14 published on Gen.xyz is quite interesting. It contains a number of numeric domain names and their Chinese meanings. I found some of the 'translations' good, for example:
44025:谢谢你爱我>Thank you for loving me 902535:求你爱我想我>Please love me and think of me 131420:一生一世爱你>There is but one lifetime and I will love you
44025 is a 5N domain name containing both 0 and 4, but it has great meaning. A jewelry brand can use it to advertise expensive diamonds for Chinese brides. Here's my point: A long numeric domain name with good Chinese meaning has value. It will be sought after by end user companies. It can be developed into a great website bringing in million dollars of sales.