Arithmetic number
![Demonstration, with Cuisenaire rods, of the arithmetic nature of the number 6](/Images/godic/202412/21/Arithmetic_number_Cuisenaire_rods_64647.png")
![](/Images/godic/202412/21/Lattice_of_the_divisibility_of_60.svg4647.png")
In number theory, an arithmetic number is an integer for which the average of its positive divisors is also an integer. For instance, 6 is an arithmetic number because the average of its divisors is
which is also an integer. However, 2 is not an arithmetic number because its only divisors are 1 and 2, and their average 3/2 is not an integer.