21100

21100 is an integer in the decimal system, located between 21099 and 21101. It is even and composite, and its prime factorization is 21100 = 2^2 × 5^2 × 211, with 211 prime.

The factorization shows that the divisors arise from choosing exponents for 2 (0–2) and 5 (0–2), together with the optional factor of 211. There are 18 positive divisors in total. A sample of small divisors includes 1, 2, 4, 5, 10, 20, 25, 50, and 100; the corresponding larger divisors are 211, 422, 844, 1055, 2110, 4220, 5275, 10550, and 21100.

The sum of all divisors of 21100 is 46004, which implies a sum of proper divisors equal to 46004 − 21100 = 24904. Since the sum of proper divisors (24904) exceeds the number itself (21100), 21100 is an abundant number. The radical of 21100, the product of its distinct prime factors, is 2 × 5 × 211 = 2110. Additionally, 21100 is divisible by 100, so it ends with two zeros.

In decimal notation, 21100 is commonly used as a plain numeric value and can appear in various practical contexts such as pricing, catalog numbers, or identifiers. In number theory, it serves as an example of a composite number with a relatively large prime factor and a square factor.