27000991 has 2 divisors, whose sum is σ = 27000992. Its totient is φ = 27000990.

The previous prime is 27000989. The next prime is 27001003. The reversal of 27000991 is 19900072.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 27000991 - 2¹ = 27000989 is a prime.

Together with 27000989, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27000901) 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 as a sum of consecutive naturals, namely, 13500495 + 13500496.

It is an arithmetic number, because the mean of its divisors is an integer number (13500496).

Almost surely, 2^27000991 is an apocalyptic number.

27000991 is a deficient number, since it is larger than the sum of its proper divisors (1).

27000991 is an equidigital number, since it uses as much as digits as its factorization.

27000991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 28.

The square root of 27000991 is about 5196.2477808511. The cubic root of 27000991 is about 300.0036703255.

The spelling of 27000991 in words is "twenty-seven million, nine hundred ninety-one", and thus it is an aban number.