2742809 has 2 divisors, whose sum is σ = 2742810. Its totient is φ = 2742808.

The previous prime is 2742799. The next prime is 2742811. The reversal of 2742809 is 9082472.

2742809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1968409 + 774400 = 1403^2 + 880^2 .

It is a cyclic number.

It is not a de Polignac number, because 2742809 - 2⁴ = 2742793 is a prime.

It is a Sophie Germain prime.

Together with 2742811, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2742889) 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, 1371404 + 1371405.

It is an arithmetic number, because the mean of its divisors is an integer number (1371405).

2^2742809 is an apocalyptic number.

It is an amenable number.

2742809 is a deficient number, since it is larger than the sum of its proper divisors (1).

2742809 is an equidigital number, since it uses as much as digits as its factorization.

2742809 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 2742809 is about 1656.1428078520. The cubic root of 2742809 is about 139.9797419668.

The spelling of 2742809 in words is "two million, seven hundred forty-two thousand, eight hundred nine".