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5181 = 311157

5181 has 8 divisors (see below), whose sum is σ = 7584. Its totient is φ = 3120.

The previous prime is 5179. The next prime is 5189. The reversal of 5181 is 1815.

Adding to 5181 its reverse (1815), we get a palindrome (6996).

It is a happy number.

5181 is nontrivially palindromic in base 6.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 5181 - 21 = 5179 is a prime.

It is a super-2 number, since 2×51812 = 53685522, which contains 22 as substring.

It is an Ulam number.

5181 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 5181.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 5181.

It is not an unprimeable number, because it can be changed into a prime (5189) 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 in 7 ways as a sum of consecutive naturals, for example, 46 + ... + 111.

It is an arithmetic number, because the mean of its divisors is an integer number (948).

It is an amenable number.

5181 is a deficient number, since it is larger than the sum of its proper divisors (2403).

5181 is a wasteful number, since it uses less digits than its factorization.

5181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171.

The product of its digits is 40, while the sum is 15.

The square root of 5181 is about 71.9791636517. The cubic root of 5181 is about 17.3036556588.

The spelling of 5181 in words is "five thousand, one hundred eighty-one".

Divisors: 1 3 11 33 157 471 1727 5181