87639890 has 32 divisors (see below), whose sum is σ = 177278976. Its totient is φ = 30951360.

The previous prime is 87639889. The next prime is 87639911. The reversal of 87639890 is 9893678.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11666 + ... + 17645.

It is an arithmetic number, because the mean of its divisors is an integer number (5539968).

Almost surely, 2^87639890 is an apocalyptic number.

87639890 is an abundant number, since it is smaller than the sum of its proper divisors (89639086).

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

87639890 is a wasteful number, since it uses less digits than its factorization.

87639890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29354.

The product of its (nonzero) digits is 653184, while the sum is 50.

The square root of 87639890 is about 9361.6179157238. The cubic root of 87639890 is about 444.1884632653.

The spelling of 87639890 in words is "eighty-seven million, six hundred thirty-nine thousand, eight hundred ninety".