2609809 has 2 divisors, whose sum is σ = 2609810. Its totient is φ = 2609808.

The previous prime is 2609791. The next prime is 2609813. The reversal of 2609809 is 9089062.

2609809 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., 2387025 + 222784 = 1545^2 + 472^2 .

It is a cyclic number.

It is not a de Polignac number, because 2609809 - 2⁵ = 2609777 is a prime.

It is a super-2 number, since 2×2609809² = 13622206032962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2609899) 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, 1304904 + 1304905.

It is an arithmetic number, because the mean of its divisors is an integer number (1304905).

2^2609809 is an apocalyptic number.

It is an amenable number.

2609809 is a deficient number, since it is larger than the sum of its proper divisors (1).

2609809 is an equidigital number, since it uses as much as digits as its factorization.

2609809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 2609809 is about 1615.4903280429. The cubic root of 2609809 is about 137.6795934240.

The spelling of 2609809 in words is "two million, six hundred nine thousand, eight hundred nine".