73 (number)

73 (seventy-three) is a number. It comes after seventy-two, but before seventy-four. 73 is the 21st prime number. Its mirror, 37, is the 12th, and its mirror, 21, is the product of multiplying seven and three and in binary, 73 is a palindrome, 1001001, which backwards is 1001001.

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