21091805

素因数分解:

$5^1\times 7^2\times {\mathrm{19}}^1\times {\mathrm{23}}^1\times {\mathrm{197}}^1$

素因数の和:258

約数の個数: 48

約数和(自身を含む): 32503680

約数和(自身を除く): 11411875

約数列:

[1, 5, 7, 19, 23, 35, 49, 95, 115, 133, 161, 197, 245, 437, 665, 805, 931, 985, 1127, 1379, 2185, 3059, 3743, 4531, 4655, 5635, 6895, 9653, 15295, 18715, 21413, 22655, 26201, 31717, 48265, 86089, 107065, 131005, 158585, 183407, 222019, 430445, 602623, 917035, 1110095, 3013115, 4218361, 21091805]

約数ペア:

[(1, 21091805), (5, 4218361), (7, 3013115), (19, 1110095), (23, 917035), (35, 602623), (49, 430445), (95, 222019), (115, 183407), (133, 158585), (161, 131005), (197, 107065), (245, 86089), (437, 48265), (665, 31717), (805, 26201), (931, 22655), (985, 21413), (1127, 18715), (1379, 15295), (2185, 9653), (3059, 6895), (3743, 5635), (4531, 4655)]