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73 (number) facts for kids

Kids Encyclopedia Facts

The number 73 (seventy-three) is a special number that comes right after seventy-two and just before seventy-four. It is known for being the 21st prime number. Prime numbers are whole numbers greater than 1 that can only be divided evenly by 1 and themselves.

What Makes 73 Special?

Prime Number Facts

As the 21st prime number, 73 holds a unique place in mathematics. Prime numbers are like the building blocks of all other numbers. The first few prime numbers are 2, 3, 5, 7, 11, and so on.

Interesting Number Properties

The number 73 has some fascinating properties:

  • Its "mirror" number, 37, is also a prime number. In fact, 37 is the 12th prime number.
  • The number 21, which is the result of multiplying 7 and 3 (the digits of 73), is also special.
  • In the binary system (a way computers count using only 0s and 1s), 73 is written as 1001001. This number is a palindrome, meaning it reads the same forwards and backwards!

See also

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73 (number) Facts for Kids. Kiddle Encyclopedia.