2551909 has 6 divisors (see below), whose sum is σ = 2693670. Its totient is φ = 2417256.

The previous prime is 2551903. The next prime is 2551933. The reversal of 2551909 is 9091552.

2551909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 2030625 + 521284 = 1425^2 + 722^2 .

It is not a de Polignac number, because 2551909 - 2⁵ = 2551877 is a prime.

It is a Duffinian number.

2551909 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2551903) 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 in 5 ways as a sum of consecutive naturals, for example, 3174 + ... + 3895.

It is an arithmetic number, because the mean of its divisors is an integer number (448945).

2^2551909 is an apocalyptic number.

It is an amenable number.

2551909 is a deficient number, since it is larger than the sum of its proper divisors (141761).

2551909 is an equidigital number, since it uses as much as digits as its factorization.

2551909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7107 (or 7088 counting only the distinct ones).

The product of its (nonzero) digits is 4050, while the sum is 31.

The square root of 2551909 is about 1597.4695615254. The cubic root of 2551909 is about 136.6538047252.

The spelling of 2551909 in words is "two million, five hundred fifty-one thousand, nine hundred nine".