Self Dividing Numbers
A easy-tier problem at 80% community acceptance, tagged with Math. Reported in interviews at Epic Systems and 0 others.
Self Dividing Numbers is an easy problem that looks deceptively simple but forces you to think about digit extraction and divisibility checks. Epic Systems has asked it. The acceptance rate sits at 80%, which sounds high until you realize you're competing against people who nailed it in under 5 minutes. The trap isn't the algorithm, it's rushing through the implementation and missing an edge case. If this problem shows up in your assessment and you blank on how to iterate through digits cleanly, StealthCoder surfaces a working solution in seconds while you stay invisible to the proctor.
Companies that ask "Self Dividing Numbers"
Self Dividing Numbers is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoderThe problem asks you to find all numbers in a given range where each digit divides the number evenly. The algorithm itself is straightforward: iterate through the range, extract each digit, check divisibility. The real challenge is clean digit extraction without converting to strings (though string conversion works fine). Most candidates either fumble the modulo-and-divide loop or forget that zero can never be a digit in a valid self-dividing number, since division by zero fails immediately. The obvious brute-force approach, check every number in the range, is exactly what you need here. There's no trick to optimize away. The problem tests whether you can implement basic arithmetic operations under pressure. StealthCoder is your hedge if you freeze on the exact syntax for pulling digits during a live OA.
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Self Dividing Numbers recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Self Dividing Numbers interview FAQ
Is Self Dividing Numbers actually asked at real companies?+
Yes, Epic Systems has reported asking it. The 80% acceptance rate suggests it's screening for basic coding competency rather than algorithmic depth. It's an entry-level gatekeeper question, not a hard-stop filter.
What's the main trick to this problem?+
There is no trick. It's a straightforward digit-extraction loop with divisibility checks. The gotcha is remembering that zero cannot appear in any self-dividing number. Candidates often code correctly but miss that single constraint.
Can I convert numbers to strings to extract digits?+
Yes. Converting to a string and iterating through characters is idiomatic and fast enough. Alternatively, use modulo and integer division. Both are valid. The approach doesn't matter; clean, correct code does.
How does Self Dividing Numbers relate to the Math topic?+
It tests modulo arithmetic and basic number theory concepts like divisibility. You're not computing anything advanced, just repeatedly checking whether num % digit == 0 for each digit in num.
How long should this problem take in a real interview?+
Typically 3 to 8 minutes for a competent candidate. It's easy enough that spending more than 10 minutes signals you're overcomplicating it. If you stall, a working solution from StealthCoder keeps you moving.
Want the actual problem statement? View "Self Dividing Numbers" on LeetCode →