Whats the smallest number ("the magic number") that can satisfy these conditions?

- its positive

- it is not divisible by any number below 20 (excluding 1)

- the average of the digits is an even number between 3 and 9

To the problem submitted by Victor Zapana

The numbers which are not divisible by any number below 20 should be prime and greater than 20. The prime numbers are 23,29,31,37,41,43,47,53,57 and so on.

The avg of digits is an even number (4,6,8)

the least number is 53

sum of the digits = 8

avg of digits=4

the solution is 53

by

Srividhya