Numbers /21,115
How rare is 21,115?
21,115 scores 507 and sits in the Extreme tier — 1 in 397 of all supported numbers score this high or higher. Everything below is computed from a complete analysis of all 1,000,001 numbers in range.
RNGdle.net’s own rarity score. Top 0.25% means that proportion of supported numbers scores at least this high. Every exact number has the same chance of being rolled. Same-length rank keeps the score and compares only numbers with 5 digits, including ties. How this differs from EP · Badge guide
These notes make the number easy to read, but they add no score unless a separately counted rarity signal appears below.
A sum 1 + 2 + … + k for some k.
Factorization · signal frequency
This number's digits add up to an uncommon total.
Arithmetic · signal frequency
Three or more identical digits in a row.
Repetition · signal frequency
This number uses an uncommon count of distinct digits.
Repetition · signal frequency
Iterating the sum of squared digits reaches 1.
Arithmetic · signal frequency
A single digit appears exactly three times.
Repetition · signal frequency
Strongest signal: Triangular number. It appears in 1,414 supported numbers and contributes +189 after correlation decay.
Why is 21,115 unusual? Only 0.25% of the 1,000,001 supported numbers receive an equal or higher rarity score. This number falls in the Extreme tier. Scoring is grounded in the exact frequency of each detected trait — rarer traits carry more information and contribute more to the score.
Algorithm version 1.1.0
One digit away
One change could reach Singular.
Your number
21,115
Extreme · Top 0.25%
Position 5: 5 → 2 · +132 points.
Gained: Digit sum 7, Palindrome, Only two distinct digits, 2 distinct digits, Harshad number.
44 legal neighbours · same digit length · no leading zeros. This describes an alternative number, not the odds of your next roll.
Explore & share this near miss →Similar interesting numbers
Explore a shared pattern, a comparable score, or a mathematical relationship. Every link explains its connection to 21,115.
Shared patterns
Same length, nearby scores
Patterns in this number
Each of these has its own page explaining how common the pattern is and why.
Triple Digits
A triple contains exactly three copies of one digit, such as 8188 or 636306. It is the most common form of strong repetition — and the first one most people notice.
Adjacent Digit Runs
A run is three or more identical digits sitting next to each other, like the 777 inside 27773. Adjacency is what makes a run read as deliberate.
Happy Numbers
Square each digit, add them up, repeat. If you eventually reach 1 the number is happy; if not, you fall into a cycle. 19 → 82 → 68 → 100 → 1.
Triangular Numbers
A triangular number counts the dots in a triangle: 1, 3, 6, 10, 15, 21 — each one the running total 1 + 2 + … + k.