2730809 has 4 divisors (see below), whose sum is σ = 2734116. Its totient is φ = 2727504.

The previous prime is 2730803. The next prime is 2730811. The reversal of 2730809 is 9080372.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1373584 + 1357225 = 1172^2 + 1165^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2730809 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2730803) 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, 767 + ... + 2459.

It is an arithmetic number, because the mean of its divisors is an integer number (683529).

2^2730809 is an apocalyptic number.

It is an amenable number.

2730809 is a deficient number, since it is larger than the sum of its proper divisors (3307).

2730809 is a wasteful number, since it uses less digits than its factorization.

2730809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3306.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 2730809 is about 1652.5159605886. The cubic root of 2730809 is about 139.7753028238.

The spelling of 2730809 in words is "two million, seven hundred thirty thousand, eight hundred nine".