By Supantha Mukherjee and Stine Jacobsen

STOCKHOLM/COPENHAGEN, July 17 (Reuters) - The Novo Nordisk Foundation and Denmark's state-owned credit fund said on Thursday they will invest in what they say will be the world's most powerful quantum computer, aiming to revolutionize areas such as drug discovery and materials science.Quantum computing holds the promise of carrying out calculations that would take today's systems millions of years and could unlock discoveries in medicine, chemistry and many other fields where near-infinite seas of possible combinations of molecules confound classical computers.

The Novo Nordisk Foundation, the non-profit which controls pharmaceutical giant Novo Nordisk NOVOb.CO, and Denmark's Export and Investment Fund (EIFO), said in a statement they would invest 80 million euros ($92.93 million) in the initiative called QuNorth.

Microsoft MSFT.O, which has its largest quantum lab in Denmark, will provide software and Atom Computing will build the quantum computer.

The computer will be named Magne, inspired by Norse mythology where Magne, the son of Thor, is known for his immense strength.

Construction will begin in autumn and the computer is expected to be ready by the end of next year.

The quantum computer will start operating with 50 logical qubits, Jason Zander, Microsoft's executive vice president, told Reuters.

A qubit, short for quantum bit, is the basic unit of information in a quantum computer and a logical qubit is a virtual qubit built from many physical qubits to reliably process quantum information.

Last November, Microsoft and Atom created 24 logical qubits, the highest number ever created.

"When we get to about 50 logical qubits, that's when we start hitting true quantum advantage," Zander said.

"I get to the point where I can run something on a quantum computer that I could not run on a classic computer."

"When the machine gets up to 100 (logical qubits), we can start doing science problems, get up to a couple 100s, we can start doing some chemistry and starting to answer things, and then when all the way up to 1,000, now you are solving everything," Zander said.

($1 = 0.8606 euros)

(Reporting by Supantha Mukherjee in Stockholm and Stine Jacobsen in CopenhagenEditing by Frances Kerry)

((supantha.mukherjee@thomsonreuters.com; +46 70 721 1004; Reuters Messaging: supantha.mukherjee.thomsonreuters.com@reuters.net))