Representation numerals

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XIII

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十三

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Numeral systems

Binary: 1101

Septimal (base 7): 16

Octal: 15

Hexadecimal: d

Base 24: D

Factorization

13 is a prime number

Sums & differences

13 is the sum of the first 2 squared prime numbers: 13 = 2^{2} + 3^{2}

Sum of 2 squares: 13 = 3^{2} + 2^{2}

Difference of 2 squares: 13 = 7^{2} - 6^{2}

Characteristics

13 is a Fibonacci number