81117 has 6 divisors (see below), whose sum is σ = 117182. Its totient is φ = 54072.

The previous prime is 81101. The next prime is 81119. The reversal of 81117 is 71118.

It can be written as a sum of positive squares in only one way, i.e., 68121 + 12996 = 261^2 + 114^2 .

It is not a de Polignac number, because 81117 - 2⁴ = 81101 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 81117.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4498 + ... + 4515.

2⁸¹¹¹⁷ is an apocalyptic number.

It is an amenable number.

81117 is a deficient number, since it is larger than the sum of its proper divisors (36065).

81117 is a wasteful number, since it uses less digits than its factorization.

81117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9019 (or 9016 counting only the distinct ones).

The product of its digits is 56, while the sum is 18.

The square root of 81117 is about 284.8104632909. The cubic root of 81117 is about 43.2883095806.

Subtracting from 81117 its reverse (71118), we obtain a palindrome (9999).

It can be divided in two parts, 8111 and 7, that added together give a palindrome (8118).

The spelling of 81117 in words is "eighty-one thousand, one hundred seventeen".