27731009 has 2 divisors, whose sum is σ = 27731010. Its totient is φ = 27731008.

The previous prime is 27730993. The next prime is 27731023. The reversal of 27731009 is 90013772.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24720784 + 3010225 = 4972^2 + 1735^2 .

It is a cyclic number.

It is not a de Polignac number, because 27731009 - 2⁴ = 27730993 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (27731059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13865504 + 13865505.

It is an arithmetic number, because the mean of its divisors is an integer number (13865505).

Almost surely, 2^27731009 is an apocalyptic number.

It is an amenable number.

27731009 is a deficient number, since it is larger than the sum of its proper divisors (1).

27731009 is an equidigital number, since it uses as much as digits as its factorization.

27731009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2646, while the sum is 29.

The square root of 27731009 is about 5266.0240219733. The cubic root of 27731009 is about 302.6833676400.

The spelling of 27731009 in words is "twenty-seven million, seven hundred thirty-one thousand, nine".