2628809 has 2 divisors, whose sum is σ = 2628810. Its totient is φ = 2628808.

The previous prime is 2628781. The next prime is 2628811. The reversal of 2628809 is 9088262.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2550409 + 78400 = 1597^2 + 280^2 .

It is a cyclic number.

It is not a de Polignac number, because 2628809 - 2⁸ = 2628553 is a prime.

It is a Sophie Germain prime.

Together with 2628811, it forms a pair of twin primes.

It is a Chen prime.

It is a d-powerful number, because it can be written as 2¹⁹ + 6³ + 2²⁰ + 8⁶ + 8⁶ + 0 + 9⁶ .

It is a Curzon number.

It is equal to p₁₉₁₇₉₈ and since 2628809 and 191798 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (2628839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1314404 + 1314405.

It is an arithmetic number, because the mean of its divisors is an integer number (1314405).

2^2628809 is an apocalyptic number.

It is an amenable number.

2628809 is a deficient number, since it is larger than the sum of its proper divisors (1).

2628809 is an equidigital number, since it uses as much as digits as its factorization.

2628809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 2628809 is about 1621.3602314107. The cubic root of 2628809 is about 138.0128987453.

The spelling of 2628809 in words is "two million, six hundred twenty-eight thousand, eight hundred nine".