27986999 has 4 divisors (see below), whose sum is σ = 28264200. Its totient is φ = 27709800.

The previous prime is 27986963. The next prime is 27987007. The reversal of 27986999 is 99968972.

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-27986999 is a prime.

It is a super-2 number, since 2×27986999² = 1566544226052002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27986909) 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, 138449 + ... + 138650.

It is an arithmetic number, because the mean of its divisors is an integer number (7066050).

Almost surely, 2^27986999 is an apocalyptic number.

27986999 is a deficient number, since it is larger than the sum of its proper divisors (277201).

27986999 is a wasteful number, since it uses less digits than its factorization.

27986999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277200.

The product of its digits is 4408992, while the sum is 59.

The square root of 27986999 is about 5290.2740004654. The cubic root of 27986999 is about 303.6118914672.

It can be divided in two parts, 279 and 86999, that added together give a palindrome (87278).

The spelling of 27986999 in words is "twenty-seven million, nine hundred eighty-six thousand, nine hundred ninety-nine".