27987187 has 4 divisors (see below), whose sum is σ = 28143720. Its totient is φ = 27830656.

The previous prime is 27987149. The next prime is 27987191. The reversal of 27987187 is 78178972.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27987187 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27987187.

It is not an unprimeable number, because it can be changed into a prime (27987587) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77998 + ... + 78355.

It is an arithmetic number, because the mean of its divisors is an integer number (7035930).

Almost surely, 2^27987187 is an apocalyptic number.

27987187 is a deficient number, since it is larger than the sum of its proper divisors (156533).

27987187 is a wasteful number, since it uses less digits than its factorization.

27987187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156532.

The product of its digits is 395136, while the sum is 49.

The square root of 27987187 is about 5290.2917688914. The cubic root of 27987187 is about 303.6125712937.

The spelling of 27987187 in words is "twenty-seven million, nine hundred eighty-seven thousand, one hundred eighty-seven".