87171989013 has 12 divisors (see below), whose sum is σ = 125918196300. Its totient is φ = 58113228096.

The previous prime is 87171988997. The next prime is 87171989033. The reversal of 87171989013 is 31098917178.

It can be written as a sum of positive squares in 2 ways, for example, as 54670389489 + 32501599524 = 233817^2 + 180282^2 .

It is not a de Polignac number, because 87171989013 - 2⁴ = 87171988997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87171989033) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 373713 + ... + 560361.

It is an arithmetic number, because the mean of its divisors is an integer number (10493183025).

Almost surely, 2^87171989013 is an apocalyptic number.

It is an amenable number.

87171989013 is a deficient number, since it is larger than the sum of its proper divisors (38746207287).

87171989013 is a wasteful number, since it uses less digits than its factorization.

87171989013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238548 (or 238545 counting only the distinct ones).

The product of its (nonzero) digits is 762048, while the sum is 54.

The spelling of 87171989013 in words is "eighty-seven billion, one hundred seventy-one million, nine hundred eighty-nine thousand, thirteen".