27681491 has 4 divisors (see below), whose sum is σ = 29309832. Its totient is φ = 26053152.

The previous prime is 27681469. The next prime is 27681523. The reversal of 27681491 is 19418672.

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

It is a cyclic number.

It is not a de Polignac number, because 27681491 - 2⁶ = 27681427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27681421) 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, 814145 + ... + 814178.

It is an arithmetic number, because the mean of its divisors is an integer number (7327458).

Almost surely, 2^27681491 is an apocalyptic number.

27681491 is a deficient number, since it is larger than the sum of its proper divisors (1628341).

27681491 is a wasteful number, since it uses less digits than its factorization.

27681491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628340.

The product of its digits is 24192, while the sum is 38.

The square root of 27681491 is about 5261.3202715668. The cubic root of 27681491 is about 302.5030976620.

The spelling of 27681491 in words is "twenty-seven million, six hundred eighty-one thousand, four hundred ninety-one".