13645

13645 is a natural number that follows 13644 and precedes 13646. In number theory, it is an odd semiprime, since it factors into two primes: 5 and 2729. Because 2729 is prime, the prime factorization is 5 × 2729, and its positive divisors are 1, 5, 2729, and 13645. This also makes 13645 a squarefree number.

The number ends with 5, so it is divisible by 5, while the sum of its digits is 19, indicating it is not divisible by 3. In different bases, 13645 has the representations: binary 11010101001101, octal 32515, and hexadecimal 0x354D. These representations reflect its factorization properties and its size relative to standard numeral systems.

In broader contexts, 13645 serves as an example of a semiprime with two distinct prime factors, a class of numbers often studied in elementary and computational number theory. Its divisors are limited, and its factorization is unique up to ordering, illustrating fundamental aspects of divisor structures in composite numbers.