3181 has 2 divisors, whose sum is σ = 3182.
Its totient is φ = 3180.
The previous prime is 3169. The next prime is 3187. The reversal of 3181 is 1813.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 2025 + 1156 = 45^2 + 34^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-3181 is a prime.
It is a super-3 number, since 3×31813 = 96563336223, which contains 333 as substring. Note that it is a super-d number also for d = 2.
It is a Chen prime.
It is a plaindrome in base 14.
It is a nialpdrome in base 15.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (3187) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1590 + 1591.
It is an arithmetic number, because the mean of its divisors is an integer number (1591).
23181 is an apocalyptic number.
It is an amenable number.
3181 is a deficient number, since it is larger than the sum of its proper divisors (1).
3181 is an equidigital number, since it uses as much as digits as its factorization.
3181 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 24, while the sum is 13.
The square root of 3181 is about 56.4003546088.
The cubic root of 3181 is about 14.7069028311.
Adding to 3181 its reverse (1813), we get a palindrome (4994).
The spelling of 3181 in words is "three thousand, one hundred eighty-one".