How many 5-digit numbers have distinct digits and are divisible by 3?
132175
How many $5$-digit numbers with distinct digits are divisible by 3 (and generalize)
117380
Divisibility Rule for 9
47550
Number of distinct arrangements {$n_i$} $n_1<n_2<n_3<n_4<n_5$ such that $\sum n_i=20$
29874
Not divisible by $2,3$ or $5$ but divisible by $7$
95141
$n^5-n$ is divisible by $10$?
70492
What is the shortest way to compute the last 3 digits of $17^{256}$?
48308
Uniqueness of radix representation of integers in base 3
58418
Does there exist a set of exactly five positive integers such that the sum of any three distinct elements is prime?
42706
How many $N$ digits binary numbers can be formed where $0$ is not repeated
108919
Numbers till 400 divisible by 2, 3, 5, 7
153892
Number Theory divisibilty
153302
$9$ divides $n-r(n)$ where $r(n)$ is $n$ with its digits reversed
44409
Number of Elements Not divisble by 3 or 5 or 7
150652
Number of 4-digit numerals with at most 2 different digits
68903
The number $2^{29}$ has exactly $9$ distinct digits. Which digit is missing?
111609
Each $2\times 5$ rectangle contains $1\times 3$ rectangle
6138
Combination of a 4-digit number