All Tools VerseGenerate Almost Perfect Numbers
Find almost perfect numbers up to a limit, whose divisors sum to one less than twice the number.
- Runs in your browser
- Nothing uploaded
- Free, no sign-up
Calculated locally in your browser. Nothing is uploaded.
How to Use Generate Almost Perfect Numbers
- Set a search limit. The highest number to check.
- Find them. The almost perfect numbers up to the limit are found.
- Read the result. They are listed in order.
- Copy the result. Click Copy result. It all runs in your browser.
Frequently Asked Questions
What is an almost perfect number?
A number whose divisors add up to exactly one less than twice the number. Every known one is a power of two.
What is the search limit for?
It sets how far the tool checks, so a larger limit finds more of them, up to two hundred thousand.
Are there any besides powers of two?
None have ever been found, which is a famous open question in number theory.
Is anything uploaded?
No. The search runs in your browser, so nothing leaves the tab.
Is it free?
Yes. Every tool here is free to use with no sign up.
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