87191804 has 24 divisors (see below), whose sum is σ = 181966848. Its totient is φ = 35742960.

The previous prime is 87191791. The next prime is 87191807. The reversal of 87191804 is 40819178.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a congruent number.

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, 67052 + ... + 68339.

It is an arithmetic number, because the mean of its divisors is an integer number (7581952).

Almost surely, 2^87191804 is an apocalyptic number.

It is an amenable number.

87191804 is an abundant number, since it is smaller than the sum of its proper divisors (94775044).

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

87191804 is a wasteful number, since it uses less digits than its factorization.

87191804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135425 (or 135423 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 87191804 is about 9337.6551660468. The cubic root of 87191804 is about 443.4301525340.

The spelling of 87191804 in words is "eighty-seven million, one hundred ninety-one thousand, eight hundred four".