5681 has 8 divisors (see below), whose sum is σ = 6720. Its totient is φ = 4752.

The previous prime is 5669. The next prime is 5683. The reversal of 5681 is 1865.

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

It is a cyclic number.

It is not a de Polignac number, because 5681 - 2¹⁰ = 4657 is a prime.

It is a super-2 number, since 2×5681² = 64547522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a zygodrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (5683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236 + ... + 258.

It is an arithmetic number, because the mean of its divisors is an integer number (840).

2⁵⁶⁸¹ is an apocalyptic number.

It is an amenable number.

5681 is a deficient number, since it is larger than the sum of its proper divisors (1039).

5681 is a wasteful number, since it uses less digits than its factorization.

5681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55.

The product of its digits is 240, while the sum is 20.

The square root of 5681 is about 75.3724087448. The cubic root of 5681 is about 17.8432898274.

It can be divided in two parts, 5 and 681, that added together give a palindrome (686).

The spelling of 5681 in words is "five thousand, six hundred eighty-one".