| 
REVERSAL-ADDITION
PALINDROME
TEST ON 
3009179
 |   
Reverse and Add Process:
  
1. Pick a number. 
2. Reverse its digits and add this value to the original number. 
3. If this is not a palindrome, go back to step 2 and repeat. 
 |  | Let's view this Reverse and Add sequence starting with 3009179: |  
3009179 
+ 9719003 
step 1: 12728182 
+ 28182721 
step 2: 40910903 
+ 30901904 
step 3: 71812807 
+ 70821817 
step 4: 142634624 
+ 426436241 
step 5: 569070865 
+ 568070965 
step 6: 1137141830 
+ 0381417311 
step 7: 1518559141 
+ 1419558151 
step 8: 2938117292 
+ 2927118392 
step 9: 5865235684 
+ 4865325685 
step 10: 10730561369 
+ 96316503701 
step 11: 107047065070 
+ 070560740701 
step 12: 177607805771 
+ 177508706771 
step 13: 355116512542 
+ 245215611553 
step 14: 600332124095 
+ 590421233006 
step 15: 1190753357101 
+ 1017533570911 
step 16: 2208286928012 
+ 2108296828022 
step 17: 4316583756034 
+ 4306573856134 
step 18: 8623157612168 
+ 8612167513268 
step 19: 17235325125436 
+ 63452152353271 
step 20: 80687477478707 
+ 70787477478608 
step 21: 151474954957315 
+ 513759459474151 
step 22: 665234414431466 
+ 664134414432566 
step 23: 1329368828864032 
+ 2304688288639231 
step 24: 3634057117503263 
+ 3623057117504363 
step 25: 7257114235007626 
+ 6267005324117527 
step 26: 13524119559125153 
+ 35152195591142531 
step 27: 48676315150267684 
+ 48676205151367684 
step 28: 97352520301635368 
+ 86353610302525379 
step 29: 183706130604160747 
+ 747061406031607381 
step 30: 930767536635768128 
+ 821867536635767039 
step 31: 1752635073271535167 
+ 7615351723705362571 
step 32: 9367986796976897738 
+ 8377986796976897639 
step 33: 17745973593953795377 
+ 77359735939537954771 
step 34: 95105709533491750148 
+ 84105719433590750159 
step 35: 179211428967082500307 
+ 703005280769824112971 
step 36: 882216709736906613278 
+ 872316609637907612288 
step 37: 1754533319374814225566 
+ 6655224184739133354571 
step 38: 8409757504113947580137 
+ 7310857493114057579048 
step 39: 15720614997228005159185 
+ 58195150082279941602751 
step 40: 73915765079507946761936 
+ 63916764970597056751937 
step 41: 137832530050105003513873 
+ 378315300501050035238731 
step 42: 516147830551155038752604 
+ 406257830551155038741615 
step 43: 922405661102310077494219 
+ 912494770013201166504229 
step 44: 1834900431115511243998448 
+ 8448993421155111340094381 
step 45: 10283893852270622584092829 
+ 92829048522607225839838201 
step 46: 103112942374877848423931030 
+ 030139324848778473249211301 
step 47: 133252267223656321673142331 
+ 133241376123656322762252331 
step 48: 266493643347312644435394662 
+ 266493534446213743346394662 
step 49: 532987177793526387781789324 
+ 423987187783625397771789235 
step 50: 956974365577151785553578559 
+ 955875355587151775563479659 
step 51: 1912849721164303561117058218 
+ 8128507111653034611279482191 
step 52: 10041356832817338172396540409 
+ 90404569327183371823865314001 
step 53: 100445926160000709996261854410 
+ 014458162699907000061629544001 
step 54: 114904088859907710057891398411 
+ 114893198750017709958880409411 
step 55: 229797287609925420016771807822 
+ 228708177610024529906782797922 
step 56: 458505465219949949923554605744 
+ 447506455329949949912564505854 
step 57: 906011920549899899836119111598 
+ 895111911638998998945029110609 
step 58: 1801123832188898898781148222207 
+ 7022228411878988988812383211081 
step 59: 8823352244067887887593531433288 
+ 8823341353957887887604422533288 
step 60: 17646693598025775775197953966576 
+ 67566935979157757752089539664671 
step 61: 85213629577183533527287493631247 
+ 74213639478272533538177592631258 
step 62: 159427269055456067065465086262505 
+ 505262680564560760654550962724951 
step 63: 664689949620016827720016048987456 
+ 654789840610027728610026949986466 
step 64: 1319479790230044556330042998973922 
+ 2293798992400336554400320979749131 
step 65: 3613278782630381110730363978723053 
+ 3503278793630370111830362878723163 
step 66: 7116557576260751222560726857446216 
+ 6126447586270652221570626757556117 
step 67: 13243005162531403444131353615002333 
+ 33320051635313144430413526150034231 
step 68: 46563056797844547874544879765036564 
 |  
  |  
 | 
3009179 takes 68 iterations / steps to resolve into a 35 digit palindrome.
 |  
  
| 
REVERSAL-ADDITION
PALINDROME
RECORDS
 |   
 
Most Delayed Palindromic Number for each digit length 
(Only iteration counts for which no smaller records exist are considered.
My program records only the smallest number that resolves for each distinct iteration count.
For example, there are 18-digit numbers that resolve in 232 iterations,
higher than the 228 iteration record shown for 18-digit numbers, but they were not recorded,
as a smaller [17-digit] number already holds the record for 232 iterations.)
  
| Digits | Number | Result |  
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
 | 
89 
187 
1,297 
10,911 
150,296 
9,008,299 
10,309,988 
140,669,390 
1,005,499,526 
10,087,799,570 
100,001,987,765 
1,600,005,969,190 
14,104,229,999,995 
100,120,849,299,260 
1,030,020,097,997,900 
10,442,000,392,399,960 
170,500,000,303,619,996 
1,186,060,307,891,929,990 
 | 
solves in 24 iterations. 
solves in 23 iterations. 
solves in 21 iterations. 
solves in 55 iterations. 
solves in 64 iterations. 
solves in 96 iterations. 
solves in 95 iterations. 
solves in 98 iterations. 
solves in 109 iterations. 
solves in 149 iterations. 
solves in 143 iterations. 
solves in 188 iterations. 
solves in 182 iterations. 
solves in 201 iterations. 
solves in 197 iterations. 
solves in 236 iterations. 
solves in 228 iterations. 
solves in 261 iterations - World Record! 
 | 
 
| [View all records] |  
  
This reverse and add program was created by Jason Doucette. 
Please visit my Palindromes and World Records page. 
You have permission to use the data from this webpage (with due credit). A link to my website is much appreciated. Thank you. 
 (This program has been run Indeterminable times since Saturday, March 9th, 2002.)
 |