Need help with the following problem :

Given an array of n integers. Count the number subsequence whose product is divisible by k. Return answer modulo 1E9 + 7.

1 <= n <= 1E5 1 <= k < 1E9 1 <= a[i] <= 1E9

I think idea is use to prime factorization but I am not able to get it completely. Is there any concept that I must learn??