1001 is a natural number that comes before 1002 and after 1000. 1001 is a palindromic number. 1001 is a composite number. 1001 is the product of the prime numbers 7, 11, and 13. If you multiply a three-digit number to 1001 it will be like the form :xyz-xyz. So, any number of the form xyz-xyz will always be a composite number.