5691 has 8 divisors (see below), whose sum is σ = 8704.
Its totient is φ = 3240.
The previous prime is 5689. The next prime is 5693. The reversal of 5691 is 1965.
It can be divided in two parts, 5 and 691, that added together give a palindrome (696).
It is an interprime number because it is at equal distance from previous prime (5689) and next prime (5693).
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 5691 - 21 = 5689 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 271 = 5691 / (5 + 6 + 9 + 1).
It is a Duffinian number.
5691 is a lucky number.
It is a plaindrome in base 13.
It is not an unprimeable number, because it can be changed into a prime (5693) 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, 115 + ... + 156.
It is an arithmetic number, because the mean of its divisors is an integer number (1088).
25691 is an apocalyptic number.
5691 is a deficient number, since it is larger than the sum of its proper divisors (3013).
5691 is a wasteful number, since it uses less digits than its factorization.
5691 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 281.
The product of its digits is 270, while the sum is 21.
The square root of 5691 is about 75.4387168502.
The cubic root of 5691 is about 17.8537532614.
The spelling of 5691 in words is "five thousand, six hundred ninety-one".