130

This number is a composite.

Just showing those entries submitted by 'Ingala': (Click here to show all)

+ 130 is the only number equal to the sum of the squares of its first 4 divisors: 130 = 1^2 + 2^2 + 5^2 + 10^2. [Ingala]

Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell