Representation numerals

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IX

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九

ט

Numeral systems

Binary: 1001

Septimal (base 7): 12

Octal: 11

Hexadecimal: 9

Base 24: 9

Factorization

9 = 3 × 3

9 has 3 divisors: 1, 3, 9

Sum of all divisors other than 9: 4

9 = 3 ^{2}

9 = 1 + 3 + 5

9 = 1 + 3 + 5

Sums & differences

Difference of 2 squares: 9 = 5^{2} - 4^{2}

Characteristics

9 is a palindromic number in decimal system

9 is a palindromic number in binary system (1001)