87137878 has 4 divisors (see below), whose sum is σ = 130706820. Its totient is φ = 43568938.

The previous prime is 87137873. The next prime is 87137881. The reversal of 87137878 is 87873178.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87137873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21784468 + ... + 21784471.

It is an arithmetic number, because the mean of its divisors is an integer number (32676705).

Almost surely, 2^87137878 is an apocalyptic number.

87137878 is a deficient number, since it is larger than the sum of its proper divisors (43568942).

87137878 is a wasteful number, since it uses less digits than its factorization.

87137878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43568941.

The product of its digits is 526848, while the sum is 49.

The square root of 87137878 is about 9334.7671636737. The cubic root of 87137878 is about 443.3387167769.

The spelling of 87137878 in words is "eighty-seven million, one hundred thirty-seven thousand, eight hundred seventy-eight".