87171918 has 16 divisors (see below), whose sum is σ = 176551680. Its totient is φ = 28689336.

The previous prime is 87171893. The next prime is 87171947. The reversal of 87171918 is 81917178.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 87171918.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91480 + ... + 92427.

It is an arithmetic number, because the mean of its divisors is an integer number (11034480).

Almost surely, 2^87171918 is an apocalyptic number.

87171918 is an abundant number, since it is smaller than the sum of its proper divisors (89379762).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87171918 is a wasteful number, since it uses less digits than its factorization.

87171918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183991.

The product of its digits is 28224, while the sum is 42.

The square root of 87171918 is about 9336.5902769694. The cubic root of 87171918 is about 443.3964386524.

The spelling of 87171918 in words is "eighty-seven million, one hundred seventy-one thousand, nine hundred eighteen".