27681813 has 12 divisors (see below), whose sum is σ = 40210560. Its totient is φ = 18350376.

The previous prime is 27681779. The next prime is 27681827. The reversal of 27681813 is 31818672.

It is not a de Polignac number, because 27681813 - 2¹⁰ = 27680789 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27681113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6981 + ... + 10202.

It is an arithmetic number, because the mean of its divisors is an integer number (3350880).

Almost surely, 2^27681813 is an apocalyptic number.

It is an amenable number.

27681813 is a deficient number, since it is larger than the sum of its proper divisors (12528747).

27681813 is a wasteful number, since it uses less digits than its factorization.

27681813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17368 (or 17365 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 27681813 is about 5261.3508721620. The cubic root of 27681813 is about 302.5042705952.

The spelling of 27681813 in words is "twenty-seven million, six hundred eighty-one thousand, eight hundred thirteen".