Representation numerals

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VII

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七

ז

Numeral systems

Binary: 111

Septimal (base 7): 10

Octal: 7

Hexadecimal: 7

Base 24: 7

Factorization

7 is a prime number (Gaussian prime)

Sums & differences

Difference of 2 squares: 7 = 4^{2} - 3^{2}

Characteristics

7 is a heptagonal number

7 is a palindromic number in decimal system

7 is a palindromic number in binary system (111)