Count of 5 Digit numbers.
65802
The number of 5-digit numbers such that their sum of digits is even is?
73307
Why is the last digit of $n^5$ equal to the last digit of $n$?
45240
Starting digits of $2^n$.
70515
Recursion and Counting
1715
Proof: How many digits does a number have? $\lfloor \log_{10} n \rfloor +1$
853
Write down the sum of sum of  sum of digits of $4444^{4444}$
49194
Given a double, need to find how many digits in total
119031
How many 6 digit numbers are possible with no digit appearing more than thrice?
154020
Write the digits of a number into an array
92968
how many element of order 2 and 5 are there
65328
Counts and skips the numbers that have digits divisible by 3 (change in base method)
116054
The number $(3+\sqrt{5})^n+(3-\sqrt{5})^n$ is an integer
92494
counting occurrence of numbers in array
74365
How to convert a one digit number to a two digit number
95755
Counting the population of integers
102368
How to calculate last four digits of $2^{2017}$?
42706
How many $N$ digits binary numbers can be formed where $0$ is not repeated