87988181 has 4 divisors (see below), whose sum is σ = 88132332. Its totient is φ = 87844032.

The previous prime is 87988163. The next prime is 87988189. The reversal of 87988181 is 18188978.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4558225 + 83429956 = 2135^2 + 9134^2 .

It is a cyclic number.

It is not a de Polignac number, because 87988181 - 2²² = 83793877 is a prime.

It is a super-2 number, since 2×87988181² = 15483839991377522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87988189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71156 + ... + 72381.

It is an arithmetic number, because the mean of its divisors is an integer number (22033083).

Almost surely, 2^87988181 is an apocalyptic number.

It is an amenable number.

87988181 is a deficient number, since it is larger than the sum of its proper divisors (144151).

87988181 is a wasteful number, since it uses less digits than its factorization.

87988181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144150.

The product of its digits is 258048, while the sum is 50.

The square root of 87988181 is about 9380.2015436770. The cubic root of 87988181 is about 444.7761041763.

The spelling of 87988181 in words is "eighty-seven million, nine hundred eighty-eight thousand, one hundred eighty-one".