27986421 has 16 divisors (see below), whose sum is σ = 39504960. Its totient is φ = 17592960.

The previous prime is 27986389. The next prime is 27986489. The reversal of 27986421 is 12468972.

27986421 is a nontrivial binomial coefficient, being equal to C(7482, 2).

It is not a de Polignac number, because 27986421 - 2⁵ = 27986389 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27986421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27986921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1 + ... + 7481.

It is an arithmetic number, because the mean of its divisors is an integer number (2469060).

It is a Poulet number, since it divides 2^27986420-1.

Almost surely, 2^27986421 is an apocalyptic number.

27986421 is the 7481-st triangular number and also the 3741-st hexagonal number.

It is an amenable number.

27986421 is a deficient number, since it is larger than the sum of its proper divisors (11518539).

27986421 is a wasteful number, since it uses less digits than its factorization.

27986421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7556.

The product of its digits is 48384, while the sum is 39.

The square root of 27986421 is about 5290.2193716329. The cubic root of 27986421 is about 303.6098013434.

The spelling of 27986421 in words is "twenty-seven million, nine hundred eighty-six thousand, four hundred twenty-one".