27887861 has 4 divisors (see below), whose sum is σ = 27908832. Its totient is φ = 27866892.

The previous prime is 27887851. The next prime is 27887863. The reversal of 27887861 is 16878872.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27887861 - 2²² = 23693557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27887863) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8345 + ... + 11198.

It is an arithmetic number, because the mean of its divisors is an integer number (6977208).

Almost surely, 2^27887861 is an apocalyptic number.

It is an amenable number.

27887861 is a deficient number, since it is larger than the sum of its proper divisors (20971).

27887861 is a wasteful number, since it uses less digits than its factorization.

27887861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20970.

The product of its digits is 301056, while the sum is 47.

The square root of 27887861 is about 5280.8958520312. The cubic root of 27887861 is about 303.2529737886.

The spelling of 27887861 in words is "twenty-seven million, eight hundred eighty-seven thousand, eight hundred sixty-one".