87890172181 has 8 divisors (see below), whose sum is σ = 100455474560. Its totient is φ = 75327260688.

The previous prime is 87890172173. The next prime is 87890172187. The reversal of 87890172181 is 18127109878.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 87890172181 - 2³ = 87890172173 is a prime.

It is a super-2 number, since 2×87890172181² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87890172187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 518241 + ... + 666598.

It is an arithmetic number, because the mean of its divisors is an integer number (12556934320).

Almost surely, 2^87890172181 is an apocalyptic number.

It is an amenable number.

87890172181 is a deficient number, since it is larger than the sum of its proper divisors (12565302379).

87890172181 is a wasteful number, since it uses less digits than its factorization.

87890172181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195443.

The product of its (nonzero) digits is 451584, while the sum is 52.

The spelling of 87890172181 in words is "eighty-seven billion, eight hundred ninety million, one hundred seventy-two thousand, one hundred eighty-one".