It is 17.
408 = 2 × 2 × 2 × 3 × 17
Sum = ½ × number of numbers × (first number + last number) = ½ × (462 - 408 + 1) × (408 + 462) = ½ × 55 × 870 = 23,925
Prime numbers are not divisible by any numbers other than themselves and 1.
The answer is 418Improved Answer:-CDVIII = 408
It is 17.
408 = 2 × 2 × 2 × 3 × 17
408 / 2204 / 2102 / 251 / 317[2 2 2 3 17] ■
408 = 2 x 2 x 2 x 3 x 17
The factors of 408 are: 1 2 3 4 6 8 12 17 24 34 51 68 102 136 204 408 The prime factors are: 2 3 17
2 x 2 x 2 x 3 x 17 = 408
408 = 2 x 2 x 2 x 3 x 17
Sum = ½ × number of numbers × (first number + last number) = ½ × (462 - 408 + 1) × (408 + 462) = ½ × 55 × 870 = 23,925
408 is an even number - as is any number which ends in 0, 2, 4, 6, 8.
No
Prime numbers are not divisible by any numbers other than themselves and 1.
The twelfth octagonal number is 408.