Palindromes and Seven
A four-digit palindrome is a number of the form $\overline{abba}$ with $a \neq 0$, such as 1221 or 7007. How many four-digit palindromes are divisible by 7? Give an integer.
Related problems & prerequisites
Worth solving first
- Square Divisors of a Factorial 4.0/10
- Trailing Zeros 3.0/10
Source: Original problem written for AxiomIQ.