20818928

素因数分解:

$2^4\times {\mathrm{13}}^1\times {\mathrm{101}}^1\times {\mathrm{991}}^1$

素因数の和:1113

約数の個数: 40

約数和(自身を含む): 43913856

約数和(自身を除く): 23094928

約数列:

[1, 2, 4, 8, 13, 16, 26, 52, 101, 104, 202, 208, 404, 808, 991, 1313, 1616, 1982, 2626, 3964, 5252, 7928, 10504, 12883, 15856, 21008, 25766, 51532, 100091, 103064, 200182, 206128, 400364, 800728, 1301183, 1601456, 2602366, 5204732, 10409464, 20818928]

約数ペア:

[(1, 20818928), (2, 10409464), (4, 5204732), (8, 2602366), (13, 1601456), (16, 1301183), (26, 800728), (52, 400364), (101, 206128), (104, 200182), (202, 103064), (208, 100091), (404, 51532), (808, 25766), (991, 21008), (1313, 15856), (1616, 12883), (1982, 10504), (2626, 7928), (3964, 5252)]