27840209 has 2 divisors, whose sum is σ = 27840210. Its totient is φ = 27840208.

The previous prime is 27840199. The next prime is 27840233. The reversal of 27840209 is 90204872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27793984 + 46225 = 5272^2 + 215^2 .

It is a cyclic number.

It is not a de Polignac number, because 27840209 - 2⁴ = 27840193 is a prime.

It is not a weakly prime, because it can be changed into another prime (27840289) 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 as a sum of consecutive naturals, namely, 13920104 + 13920105.

It is an arithmetic number, because the mean of its divisors is an integer number (13920105).

Almost surely, 2^27840209 is an apocalyptic number.

It is an amenable number.

27840209 is a deficient number, since it is larger than the sum of its proper divisors (1).

27840209 is an equidigital number, since it uses as much as digits as its factorization.

27840209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 27840209 is about 5276.3821885834. The cubic root of 27840209 is about 303.0801524894.

The spelling of 27840209 in words is "twenty-seven million, eight hundred forty thousand, two hundred nine".