6621

6621 is a natural number that follows 6620 and precedes 6622. In mathematics, 6621 is an odd composite number. Its prime factorization is 3 × 7 × 313, indicating that it has six positive divisors: 1, 3, 7, 21, 313, and 6621 itself. The sum of its proper divisors is 345, which classifies 6621 as a deficient number because the sum is less than the number. In base‑10 representation, the digits 6, 6, 2, and 1 appear in a pattern that occasionally draws interest in recreational numerology, though no special significance is widely recognized.

In astronomy, the designation 6621 appears in the cataloguing of minor planets; for example, asteroid 6621 was discovered in the 1990s and is a main‑belt asteroid with an orbital period of approximately 4.4 Earth years. The asteroid’s provisional designation and subsequent naming follow the conventions of the International Astronomical Union.

The number also occurs in transportation and infrastructure contexts. In the United States, several state routes and county highways bear the number 6621, typically serving local traffic. In telecommunications, 6621 can appear as part of a telephone exchange prefix in certain regions, though it does not correspond to a specific national standard.

Culturally, 6621 does not hold widespread symbolic meaning, but it may appear in catalog numbers, product model identifiers, and as a numeric code in various administrative systems. Its presence across different domains illustrates the routine use of sequential numbering in organizational practices.