18646

18646 is a natural number that follows 18645 and precedes 18647. Its prime factorization is 2 x 3 x 3107. In Roman numerals, it is represented as XVIII DC XL VI. The number 18646 can be expressed as the sum of two squares: 125^2 + 69^2. It is also a happy number in base 10, meaning that if you repeatedly replace the number by the sum of the squares of its digits, you eventually reach 1. The sequence is 1^2 + 8^2 + 6^2 + 4^2 + 6^2 = 1 + 64 + 36 + 16 + 36 = 153. Then 1^2 + 5^2 + 3^2 = 1 + 25 + 9 = 35. Next, 3^2 + 5^2 = 9 + 25 = 34. Following this, 3^2 + 4^2 = 9 + 16 = 25. Finally, 2^2 + 5^2 = 4 + 25 = 29. Oh wait, 29 is not a happy number. My apologies, 18646 is not a happy number. Let me recheck. The sequence actually leads to a cycle: 18646 -> 153 -> 35 -> 34 -> 25 -> 29 -> 85 -> 89 -> 145 -> 42 -> 20 -> 4 -> 16 -> 37 -> 58 -> 89. The number 18646 itself does not appear to hold any widely recognized special properties in mathematics or other fields of common knowledge.

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