9181 has 2 divisors, whose sum is σ = 9182. Its totient is φ = 9180.

The previous prime is 9173. The next prime is 9187. The reversal of 9181 is 1819.

9181 is nontrivially palindromic in base 9.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8281 + 900 = 91^2 + 30^2 .

It is a cyclic number.

It is not a de Polignac number, because 9181 - 2³ = 9173 is a prime.

It is a super-2 number, since 2×9181² = 168581522, which contains 22 as substring.

It is a Chen prime.

It is a pancake number, because a pancake can be divided into 9181 parts by 135 straight cuts.

9181 is a lucky number.

It is a plaindrome in base 14 and base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4590 + 4591.

It is an arithmetic number, because the mean of its divisors is an integer number (4591).

2⁹¹⁸¹ is an apocalyptic number.

It is an amenable number.

9181 is a deficient number, since it is larger than the sum of its proper divisors (1).

9181 is an equidigital number, since it uses as much as digits as its factorization.

9181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 19.

The square root of 9181 is about 95.8175349297. The cubic root of 9181 is about 20.9393564107.

It can be divided in two parts, 918 and 1, that added together give a palindrome (919).

The spelling of 9181 in words is "nine thousand, one hundred eighty-one".