20421

20421 is a natural number that follows 20420 and precedes 20422. It is an odd, composite integer with several notable arithmetic properties.

In its prime factorization, 20421 = 3^2 × 2269, where 2269 is a prime number. This factorization gives 20421 a total of (2+1)×(1+1) = 6 divisors: 1, 3, 9, 2269, 6807, and 20421. The digit sum of 20421 is 9, so the number is divisible by 9 (20421 ÷ 9 = 2269). Consequently, 20421 is a Harshad number in base 10, meaning it is divisible by the sum of its digits.

Representations of 20421 include its binary and hexadecimal forms. In binary, it is 100111111000101, a 15-bit string. In hexadecimal, 20421 equals 0x4FC5.

Additional observations include its non-triangular status; solving for whether 20421 is a triangular number yields a non-integer solution. While 20421 does not have widely noted special status in most standard number-theory catalogs, its factorization and Harshad property make it a representative example of a composite number with a simple squared prime factor and a larger prime cofactor. In practical contexts, 20421 can serve as a generic numeric identifier or label in datasets, catalogs, or coding schemes, independent of any particular historical or mathematical significance.