87191808 has 72 divisors (see below), whose sum is σ = 253178016. Its totient is φ = 26419200.

The previous prime is 87191807. The next prime is 87191821. The reversal of 87191808 is 80819178.

It is a super-2 number, since 2×87191808² = 15204822764617728, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 87191808.

It is not an unprimeable number, because it can be changed into a prime (87191807) 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, 3288 + ... + 13608.

Almost surely, 2^87191808 is an apocalyptic number.

87191808 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 87191808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126589008).

87191808 is an abundant number, since it is smaller than the sum of its proper divisors (165986208).

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

87191808 is a wasteful number, since it uses less digits than its factorization.

87191808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10351 (or 10337 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 42.

The square root of 87191808 is about 9337.6553802333. The cubic root of 87191808 is about 443.4301593149.

The spelling of 87191808 in words is "eighty-seven million, one hundred ninety-one thousand, eight hundred eight".