9999 (number)

9999 (Nine Thousand Nine Hundred and Ninety-Nine) is a natural number that follows 9998 and precedes 10000.

Properties:

• It is a composite number.
• Its prime factorization is 3 x 3 x 11 x 101.
• The divisors of 9999 are 1, 3, 9, 11, 33, 99, 101, 303, 909, 1111, 3333, and 9999. Therefore, the sum of its proper divisors is 5812, making it a deficient number.
• 9999 is divisible by the repdigit 1111.
• It is four less than 10003, the smallest 5-digit prime number.
• It is one less than ten thousand (10,000).

Significance:

• 9999 can represent a near-maximum quantity or value in certain contexts, particularly where a four-digit representation is used.
• It is a symmetrical number (a palindrome).
• In some contexts, 9999 may represent an end-of-range value or a special code.

Representations:

• In Roman numerals, it is represented as ⅮⅯⅯⅯCMXCIX. (Although strictly speaking, the use of MMMM is acceptable but less conventional than using overlines).