2309805 has 12 divisors (see below), whose sum is σ = 4003740. Its totient is φ = 1231872.

The previous prime is 2309803. The next prime is 2309837. The reversal of 2309805 is 5089032.

It can be written as a sum of positive squares in 2 ways, for example, as 1483524 + 826281 = 1218^2 + 909^2 .

It is not a de Polignac number, because 2309805 - 2¹ = 2309803 is a prime.

2309805 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2309803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25620 + ... + 25709.

It is an arithmetic number, because the mean of its divisors is an integer number (333645).

2^2309805 is an apocalyptic number.

It is an amenable number.

2309805 is a deficient number, since it is larger than the sum of its proper divisors (1693935).

2309805 is a wasteful number, since it uses less digits than its factorization.

2309805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51340 (or 51337 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 2309805 is about 1519.8042637129. The cubic root of 2309805 is about 132.1879210456.

The spelling of 2309805 in words is "two million, three hundred nine thousand, eight hundred five".