Representation numerals

ϟαʹ

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XCI

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九十一

צא

Numeral systems

Binary: 1011011

Septimal (base 7): 160

Octal: 133

Hexadecimal: 5b

Base 24: 3J

Sums & differences

Difference of 2 squares: 91 = 10^{2} - 3^{2} = 46^{2} - 45^{2}

Characteristics

91 is a triangular number

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The next triangular is: 105

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The next triangular is: 105

91 is a hexagonal number