87938181 has 6 divisors (see below), whose sum is σ = 127021830. Its totient is φ = 58625448.

The previous prime is 87938171. The next prime is 87938189. The reversal of 87938181 is 18183978.

It can be written as a sum of positive squares in only one way, i.e., 87721956 + 216225 = 9366^2 + 465^2 .

It is not a de Polignac number, because 87938181 - 2⁶ = 87938117 is a prime.

It is a super-2 number, since 2×87938181² = 15466247355177522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87938189) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4885446 + ... + 4885463.

It is an arithmetic number, because the mean of its divisors is an integer number (21170305).

Almost surely, 2^87938181 is an apocalyptic number.

It is an amenable number.

87938181 is a deficient number, since it is larger than the sum of its proper divisors (39083649).

87938181 is a wasteful number, since it uses less digits than its factorization.

87938181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9770915 (or 9770912 counting only the distinct ones).

The product of its digits is 96768, while the sum is 45.

The square root of 87938181 is about 9377.5359770038. The cubic root of 87938181 is about 444.6918389991.

It can be divided in two parts, 879 and 38181, that added together give a triangular number (39060 = T₂₇₉).

The spelling of 87938181 in words is "eighty-seven million, nine hundred thirty-eight thousand, one hundred eighty-one".