Convert disintegrations per minute to curie

The becquerel is one decay per second, a very small unit: the potassium-40 in a banana comes to about 15 Bq and a human body to some 4,000 Bq of potassium-40 plus 3,000 Bq of carbon-14. The curie is the activity of one gram of radium-226, 3.7 × 10¹⁰ Bq, and is still the working unit in the United States; a household smoke detector holds about 1 µCi (37 kBq) of americium-241, and nuclear medicine doses are quoted in mCi or MBq. The rutherford, one million becquerels, is obsolete.