Dec 22 (Reuters) - Allianz Real Estate said on Wednesday it had invested 7.9 billion Swedish crowns ($870.88 million) in Heimstaden Bostad"s (HEIMpref.ST) portfolio of properties in Sweden that it recently acquired from its rival Akelius Residential Properties (AKELd.ST). The agreement will form a joint venture on the 30.4 billion Swedish crown portfolio, which includes 3,377 homes in Malmo and 5,932 homes in Stockholm, the asset manager said in a statement. Allianz Real Estate, on behalf of insurer Allianz (ALVG.DE), said the joint venture will be funded with equity, as well as a debt facility from Heimstaden. Heimstaden in September agreed to buy Akelius" 599 properties in Germany, Denmark and Sweden for 92.5 billion Swedish crowns ($10.6 billion), following a string of smaller portfolio acquisitions this year across northern and central Europe. ($1 = 9.0713 Swedish crowns)