87861 has 4 divisors (see below), whose sum is σ = 117152. Its totient is φ = 58572.

The previous prime is 87853. The next prime is 87869. The reversal of 87861 is 16878.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (87853) and next prime (87869).

It is not a de Polignac number, because 87861 - 2³ = 87853 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87869) 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, 14641 + ... + 14646.

It is an arithmetic number, because the mean of its divisors is an integer number (29288).

2⁸⁷⁸⁶¹ is an apocalyptic number.

It is an amenable number.

87861 is a deficient number, since it is larger than the sum of its proper divisors (29291).

87861 is a wasteful number, since it uses less digits than its factorization.

87861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29290.

The product of its digits is 2688, while the sum is 30.

The square root of 87861 is about 296.4135624427. The cubic root of 87861 is about 44.4561702857.

It can be divided in two parts, 878 and 61, that added together give a palindrome (939).

The spelling of 87861 in words is "eighty-seven thousand, eight hundred sixty-one".