420521

420521 is a six‑digit numeric code that appears in a number of unrelated contexts, each of which has emerged independently in different industries. In its most common use, 420521 is the numerical designator employed by a major American telecommunications firm as part of the internal routing system for certain long‑distance customer accounts that were established during the early 2000s. The code appears in database entries, billing records, and service call documentation and is used only for administrative purposes, carrying no public-facing significance.

In a completely separate domain, the same sequence operates as a model number for a line of industrial barcode scanners issued by a German manufacturer between 2005 and 2010. The scanners were marketed under the designation “Batch 420521”, and the numbering was incorporated into spare‑parts catalogues, technical support manuals, and warranty claim forms. The five‑digit suffix, “0521”, denotes the year of production (2010), while the preceding “420” indicates the internal production batch.

The sequence has also appeared in a handful of consumer electronics product listings, most notably as a part of the product code for a mid‑tier digital camera released in 2008. In that context the full code was 420‑521‑A, and the “520” series of models was assigned by the manufacturer’s internal trail‑numbering scheme.

Because the number is used only as a proprietary identifier, it has no standardized definition or meaning beyond the specific company contexts in which it is applied. As a result, references to 420521 in public documents are usually limited to internal company documentation or to third‑party technology support sites, and the term does not have a recognized encyclopedic significance outside of those specialized uses.