27489991 has 4 divisors (see below), whose sum is σ = 28685232. Its totient is φ = 26294752.

The previous prime is 27489983. The next prime is 27489997. The reversal of 27489991 is 19998472.

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 27489991 - 2³ = 27489983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27489997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 597586 + ... + 597631.

It is an arithmetic number, because the mean of its divisors is an integer number (7171308).

Almost surely, 2^27489991 is an apocalyptic number.

27489991 is a deficient number, since it is larger than the sum of its proper divisors (1195241).

27489991 is a wasteful number, since it uses less digits than its factorization.

27489991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1195240.

The product of its digits is 326592, while the sum is 49.

The square root of 27489991 is about 5243.0898332949. The cubic root of 27489991 is about 301.8039127364.

The spelling of 27489991 in words is "twenty-seven million, four hundred eighty-nine thousand, nine hundred ninety-one".