This question was asked at [MSE][1] but recieved no attention at all. Here it is: Are there finitely many $(n,k) \in \mathbb{N}^2$ with $2^n-1=p_1p_2\cdots p_k$ ? $p_1=3,p_2=5 , ...,p_k$ are consecutive odd primes in ascending order. An example is when $n=4, k=2$: $2^4-1=3\cdot 5=p_1p_2$ Are there finitely many $n$? I tried to use [Zsigmondy's theorem][2] without success. Thanks in advance! [1]: https://math.stackexchange.com/questions/1465274/is-2n-1-finitely-many-times-the-product-of-consecutive-primes [2]: https://en.wikipedia.org/wiki/Zsigmondy%27s_theorem