87891 has 4 divisors (see below), whose sum is σ = 117192. Its totient is φ = 58592.

The previous prime is 87887. The next prime is 87911. The reversal of 87891 is 19878.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 87891 - 2² = 87887 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (87811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14646 + ... + 14651.

It is an arithmetic number, because the mean of its divisors is an integer number (29298).

2⁸⁷⁸⁹¹ is an apocalyptic number.

87891 is the 188-th centered pentagonal number.

87891 is a deficient number, since it is larger than the sum of its proper divisors (29301).

87891 is a wasteful number, since it uses less digits than its factorization.

87891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29300.

The product of its digits is 4032, while the sum is 33.

The square root of 87891 is about 296.4641630956. The cubic root of 87891 is about 44.4612295397.

It can be divided in two parts, 878 and 91, that added together give a palindrome (969).

The spelling of 87891 in words is "eighty-seven thousand, eight hundred ninety-one".