87218 has 4 divisors (see below), whose sum is σ = 130830. Its totient is φ = 43608.

The previous prime is 87211. The next prime is 87221. The reversal of 87218 is 81278.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81278 = 2 ⋅40639.

It can be written as a sum of positive squares in only one way, i.e., 85849 + 1369 = 293^2 + 37^2 .

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (87211) by changing a digit.

87218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21803 + ... + 21806.

2⁸⁷²¹⁸ is an apocalyptic number.

87218 is a deficient number, since it is larger than the sum of its proper divisors (43612).

87218 is a wasteful number, since it uses less digits than its factorization.

87218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43611.

The product of its digits is 896, while the sum is 26.

The square root of 87218 is about 295.3269374778. The cubic root of 87218 is about 44.3474556299.

The spelling of 87218 in words is "eighty-seven thousand, two hundred eighteen".