The number two is the only whole number factor of 64 because factors must be prime numbers, and all of the divisors of 64 except for the number one are divisible by two. The number 64 has four one-digit divisors, including one, two, four and eight. It also has three two-digit divisors, including 16, 32 and 64. It is the lowest positive number with seven divisors.
Mathematicians can also express 64 as a power of some of its divisors. It is equal to two raised to the sixth power, four raised to the third power and eight squared. It is the lowest positive number that is both a perfect square and a perfect cube.
The number 64 is also a centered triangular number. This means that it can be expressed by a series of triangles, in this case seven, centered around one dot. Three dots form the smallest triangle. Six dots form the middle triangle. Nine dots form the next triangle, and so on. The seventh outer triangle has 18 dots. The sum of the central dot and all the dots in all seven triangles, one plus three plus six plus nine plus 12 plus 15 plus 18, equals 64.