What are the numbers divisible by 399?

399, 798, 1197, 1596, 1995, 2394, 2793, 3192, 3591, 3990, 4389, 4788, 5187, 5586, 5985, 6384, 6783, 7182, 7581, 7980, 8379, 8778, 9177, 9576, 9975, 10374, 10773, 11172, 11571, 11970, 12369, 12768, 13167, 13566, 13965, 14364, 14763, 15162, 15561, 15960, 16359, 16758, 17157, 17556, 17955, 18354, 18753, 19152, 19551, 19950, 20349, 20748, 21147, 21546, 21945, 22344, 22743, 23142, 23541, 23940, 24339, 24738, 25137, 25536, 25935, 26334, 26733, 27132, 27531, 27930, 28329, 28728, 29127, 29526, 29925, 30324, 30723, 31122, 31521, 31920, 32319, 32718, 33117, 33516, 33915, 34314, 34713, 35112, 35511, 35910, 36309, 36708, 37107, 37506, 37905, 38304, 38703, 39102, 39501, 39900, 40299, 40698, 41097, 41496, 41895, 42294, 42693, 43092, 43491, 43890, 44289, 44688, 45087, 45486, 45885, 46284, 46683, 47082, 47481, 47880, 48279, 48678, 49077, 49476, 49875, 50274, 50673, 51072, 51471, 51870, 52269, 52668, 53067, 53466, 53865, 54264, 54663, 55062, 55461, 55860, 56259, 56658, 57057, 57456, 57855, 58254, 58653, 59052, 59451, 59850, 60249, 60648, 61047, 61446, 61845, 62244, 62643, 63042, 63441, 63840, 64239, 64638, 65037, 65436, 65835, 66234, 66633, 67032, 67431, 67830, 68229, 68628, 69027, 69426, 69825, 70224, 70623, 71022, 71421, 71820, 72219, 72618, 73017, 73416, 73815, 74214, 74613, 75012, 75411, 75810, 76209, 76608, 77007, 77406, 77805, 78204, 78603, 79002, 79401, 79800, 80199, 80598, 80997, 81396, 81795, 82194, 82593, 82992, 83391, 83790, 84189, 84588, 84987, 85386, 85785, 86184, 86583, 86982, 87381, 87780, 88179, 88578, 88977, 89376, 89775, 90174, 90573, 90972, 91371, 91770, 92169, 92568, 92967, 93366, 93765, 94164, 94563, 94962, 95361, 95760, 96159, 96558, 96957, 97356, 97755, 98154, 98553, 98952, 99351, 99750

There is a total of 250 numbers (up to 100000) that are divisible by 399.
The sum of these numbers is 12518625.
The arithmetic mean of these numbers is 50074.5.

How to find the numbers divisible by 399?

Finding all the numbers that can be divided by 399 is essentially the same as searching for the multiples of 399: if a number N is a multiple of 399, then 399 is a divisor of N.

Indeed, if we assume that N is a multiple of 399, this means there exists an integer k such that:

$k \times 399 = N$

Conversely, the result of N divided by 399 is this same integer k (without any remainder):

$k = \frac{N}{399}$

From this we can see that, theoretically, there's an infinite quantity of multiples of 399 (we can keep multiplying it by increasingly larger integers, without ever reaching the end).

However, in this instance, we've chosen to set an arbitrary limit (specifically, the multiples of 399 less than 100000):

1 × 399 = 399
2 × 399 = 798
3 × 399 = 1197
...
249 × 399 = 99351
250 × 399 = 99750