3621

3621 is a natural number that follows 3620 and precedes 3622. It is odd and composite, with prime factorization 3 × 17 × 71, making it square-free. The eight positive divisors are 1, 3, 17, 51, 71, 213, 1207, and 3621. The sum of its divisors is 5184, and the aliquot sum is 1563. Because the sum of digits is 12, 3621 is divisible by 3 but not by 9.

In various numeral systems, 3621 is represented as decimal 3621, hexadecimal 0xE25, and binary 111000100101. In Roman numerals it is written MMMDCXXI, and it can be viewed as near a square, since 60^2 equals 3600 and 3621 is 21 more.

As a cardinal number, 3621 is used in mathematical contexts to illustrate properties of factorization, divisors, and modular arithmetic. It may also appear as an identifying label in catalogs, inventories, or datasets, separate from its mathematical significance. The number’s factorization into three distinct primes and its divisor structure make it a concrete example for teaching basic number theory concepts.