6638

6638 is a natural number that follows 6637 and precedes 6639. In mathematics, it is even and composite. Its prime factorization is 2 × 3319, and since 3319 is prime, 6638 is a semiprime, the product of two primes.

The sum of its proper divisors is 1 + 2 + 3319 = 3222, which is less than 6638, so 6638 is a deficient number (it does not equal the sum of its proper divisors). The digits of 6638 sum to 23, giving a digital root of 5. Consequently, 6638 is not a Harshad number, since it is not divisible by the sum of its digits.

In other numeral systems, 6638 appears as follows: binary 1100111101110, octal 14756, and hexadecimal 0x19EE.

As a relatively small integer, 6638 serves as an example in discussions of semiprimes and even numbers. It has a straightforward factorization, a simple divisor structure, and familiar representations across common bases, making it a useful reference point in elementary number theory. There is no widely noted cultural or historical significance attached to the number itself.