I divisori di 1981990 sono 16, elencati qui di seguito: 1; 2; 5; 10; 47; 94; 235; 470; 4217; 8434; 21085; 42170; 198199; 396398; 990995; 1981990
1981971, 1981972, 1981973, 1981974, 1981975, 1981976, 1981977, 1981978, 1981979, 1981980, 1981981, 1981982, 1981983, 1981984, 1981985, 1981986, 1981987, 1981988, 1981989, 1981991, 1981992, 1981993, 1981994, 1981995, 1981996, 1981997, 1981998, 1981999, 1982000, 1982001, 1982002, 1982003, 1982004, 1982005, 1982006, 1982007, 1982008, 1982009