Computed with engine art-1.0.0. Data updated: 2026-09-26 (UTC). Rules independently implemented by RNGDLE.ART.
Also known as: Palindromic number
Symmetry
Rule, exact count and rarity
A decimal palindrome reads identically from left to right and from right to left. Corresponding outside digits must agree, so the first half determines the mirrored half; an odd-length number has a free middle digit. RNGDLE.ART requires at least two decimal digits for this badge. That convention excludes single-digit values even though they are often considered palindromes in broader mathematical usage. No leading zeros are supplied: 10 does not become 010. Every decimal repdigit is a palindrome under this rule, but a palindrome such as 1221 need not be a repdigit. Decimal symmetry is independent of binary symmetry, and being palindromic alone does not specify primality, divisibility or the final rarity score.
The exact count, 1,989, comes from evaluating all 1,000,001 integers from 0 through 1,000,000, including both endpoints. It is not a sample or an estimate. Each matching integer is counted once for this category, even if it contains multiple qualifying segments. Its frequency of 0.1989% describes the chance that a uniformly chosen integer passes this one test. It is not the global score percentile of every member, and overlapping pattern counts must not be added as if they represented disjoint sets.
The pattern supplies −log₂(1,989 / 1,000,001) bits before its within-family weight is applied. Other matched patterns, digit sum, distinct-digit count and short-length signals can change the complete score. Consequently, members of this category need not share a ranking. The highest-scoring representative is 55, with a rarity score of 1,377 and Top 0.0006%. This uses its complete score across all features, not just this pattern. Equal scores are displayed in ascending numerical order.
Example numbers
ExploreThe highest-scoring match
The highest-scoring representative is 55, with a rarity score of 1,377 and Top 0.0006%. This uses its complete score across all features, not just this pattern. Equal scores are displayed in ascending numerical order.
Frequently asked questions
How many palindrome numbers are there between 0 and 1,000,000?
There are exactly 1,989 matches for palindrome numbers among the 1,000,001 integers from 0 to 1,000,000, inclusive: 0.1989% of the range. Two or more digits read the same in either direction.
Is 0 a palindrome number?
In the usual broad definition, a single digit reads the same backwards. RNGDLE.ART's palindrome badge deliberately starts at two digits, so 0 and the other single-digit values are not counted here.
What is the highest-scoring palindrome numbers representative?
The highest-scoring representative is 55, with a rarity score of 1,377 and Top 0.0006%. This uses its complete score across all features, not just this pattern. Equal scores are displayed in ascending numerical order.