27987864 has 32 divisors (see below), whose sum is σ = 70398720. Its totient is φ = 9272096.

The previous prime is 27987809. The next prime is 27987877. The reversal of 27987864 is 46878972.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 517 + ... + 7499.

It is an arithmetic number, because the mean of its divisors is an integer number (2199960).

Almost surely, 2^27987864 is an apocalyptic number.

27987864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

27987864 is an abundant number, since it is smaller than the sum of its proper divisors (42410856).

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

27987864 is a wasteful number, since it uses less digits than its factorization.

27987864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7159 (or 7155 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 51.

The square root of 27987864 is about 5290.3557536332. The cubic root of 27987864 is about 303.6150193670.

The spelling of 27987864 in words is "twenty-seven million, nine hundred eighty-seven thousand, eight hundred sixty-four".