[QUOTE=akruppa;128508]Here's another good page to factor numbers: [url]http://www.alpertron.com.ar/ECM.HTM[/url][/QUOTE]That page ain't so good because it needs either java or javascript to work.

sory but i need a big prime checker
 

thanks for the last prime checker but now I need a 149 number.
can someone help me?
67039039649712985497870124991029230637396829102961966888617807218608820150367734884009371490834517138450159290932430254268769414059732849732168245030420479

[quote=n1994;128544]thanks for the last prime checker but now I need a 149 number.
can someone help me?
[number clipped out][/quote]
[URL]http://pari.math.u-bordeaux.fr/download.html[/URL]
Try using PARI/GP to factor your numbers. Use the factor(x) command (or, if you only need to know primality, use isprime(x), or ispseudoprime(x) if you want it faster but don't need to be 100% sure it's correct).
Why do you need to know if all these numbers are prime or not?

That number has 155 digits. Coincidentally, it contains a 149 digit (probable) prime

the small factors are:
691 and 8941

ohh i counted 149 and are u sure its not prime?

please can someone give me a softare
161585030356555036503574383443349759802220513348577420160651727137623275694339454465986007057614567318443589804609490097470597795752454605475440761932241415603154386836504980458750988751948260533980288191920337841383961093213098780809190471692380852352908229260181525214437879457705329043037761995619651927609571666948341712103424873932822847474280880176631610290389028296655130963542301570751292964320885583629718018592309286787991755761508229522018488066166436156135628423554101048625785508634656617348392712903283489675229986341764993191077625831947186677718010677166148023226592393024760740967779268055297981153279

[quote=n1994;128559]please can someone give me a softare
161585030356555036503574383443349759802220513348577420160651727137623275694339454465986007057614567318443589804609490097470597795752454605475440761932241415603154386836504980458750988751948260533980288191920337841383961093213098780809190471692380852352908229260181525214437879457705329043037761995619651927609571666948341712103424873932822847474280880176631610290389028296655130963542301570751292964320885583629718018592309286787991755761508229522018488066166436156135628423554101048625785508634656617348392712903283489675229986341764993191077625831947186677718010677166148023226592393024760740967779268055297981153279[/quote]
I already have. PARI/GP.
[url]http://pari.math.u-bordeaux.fr/download.html[/url]
Download it. It's not that hard to use.

but it doesnt let me download it
 

???

[quote=n1994;128558]ohh i counted 149 and are u sure its not prime?[/quote]

you counted? as in by sight, digit by digit? Bravo to your patience, if so, but I'll trust my program which says 155 digits.

I'm sure its not. It has the factors I stated. You can check this for yourself using the program mentioned in this thread, or use bc ([URL]http://gnuwin32.sourceforge.net/packages/bc.htm[/URL]).

[edit]
your last (annoyingly, for my browser) long number is also not prime.

[quote=n1994;128562]???[/quote]
[URL]http://pari.math.u-bordeaux.fr/pub/pari/windows/Pari-2-3-3.exe[/URL]
1. Download that.
2. Install it.
3. Run gp.exe.
4. Type "isprime(", then copy your long number and paste it in by clicking the C:\ icon in the upper left corner, going to Edit, and clicking Paste (Ctrl+V doesn't work in GP, and right click is disabled), then press ")" and click Enter.
5. See that it says 0, meaning not prime.
6. Stop posting here about things you can obviously find on your own.
If you do need to post another long number, please use the [ code ][ /code ] tags so it doesn't make the page extremely long.

[quote=Mini-Geek;128567][URL]http://pari.math.u-bordeaux.fr/pub/pari/windows/Pari-2-3-3.exe[/URL]
1. Download that.
2. Install it.
3. Run gp.exe.
4. Type "isprime(", then copy your long number and paste it in by clicking the C:\ icon in the upper left corner, going to Edit, and clicking Paste (Ctrl+V doesn't work in GP, and right click is disabled), then press ")" and click Enter.
5. See that it says 0, meaning not prime.
6. Stop posting here about things you can obviously find on your own.
If you do need to post another long number, please use the [ code ][ /code ] tags so it doesn't make the page extremely long.[/quote]

thanks last problem' can i copy anumber into it with out writing it