Solution:
We know that the number of factors of these two numbers is 15 . We know that the factors of 15 are 1,3,5, and 15.
The number of factors of N is (p+1)⋅(q+1) (Where, N=ap⋅bq, and a,b are prime numbers).
Hence, the value of N will be least when (p+1) and (q+1) are as close as possible and a, and b are the least distinct prime numbers.
Hence, p+1=3⇒p=2, and q+1=5⇒q=4, and the prime numbers a, and b are 2 , and 3 , respectively.
Hence, the lowest value of N is N=24×32=144, and the second lowest value of N is N=22×34= 324.
Hence, the sum is (144+324)=468
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