27891 has 8 divisors (see below), whose sum is σ = 41360. Its totient is φ = 18576.

The previous prime is 27883. The next prime is 27893. The reversal of 27891 is 19872.

It is not a de Polignac number, because 27891 - 2³ = 27883 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1033 = 27891 / (2 + 7 + 8 + 9 + 1).

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27893) 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, 490 + ... + 543.

It is an arithmetic number, because the mean of its divisors is an integer number (5170).

2²⁷⁸⁹¹ is an apocalyptic number.

27891 is a deficient number, since it is larger than the sum of its proper divisors (13469).

27891 is a wasteful number, since it uses less digits than its factorization.

27891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1042 (or 1036 counting only the distinct ones).

The product of its digits is 1008, while the sum is 27.

The square root of 27891 is about 167.0059879166. The cubic root of 27891 is about 30.3264351204.

The spelling of 27891 in words is "twenty-seven thousand, eight hundred ninety-one".