Translation:My income is more than ten million in one month.
Not necessarily true though. For those who aren't salaried, you could have a very good month where you make more than ten million but make half that the next month, etc. But you might not make more than ten million each month.
Maybe the difference is "sepuluh juta sebulan" (ten million a month) vs "sepuluh juta dalam satu bulan" (ten million in one month)? I don't know whether there are slight differences in semantics, or if those two sentences mean the exact same thing...
If that were the case, I would find it more natural to say “this month” or “that month”.
Or use something other than the present simple. "I made ten million rupiah in one month" makes sense, especially if you're trying to emphasise how fast you made so much money.
It's al about the context, isn't it. I take the sentence in Indonesian to mean income as in regular monthly income. So, "My income is more than ten million a month" or "per month" should be acceptable.