2005646605 has 24 divisors (see below), whose sum is σ = 2496434472. Its totient is φ = 1546739712.

The previous prime is 2005646597. The next prime is 2005646623. The reversal of 2005646605 is 5066465002.

It can be written as a sum of positive squares in 12 ways, for example, as 155700484 + 1849946121 = 12478^2 + 43011^2 .

It is not a de Polignac number, because 2005646605 - 2³ = 2005646597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 772189 + ... + 774781.

It is an arithmetic number, because the mean of its divisors is an integer number (104018103).

Almost surely, 2^2005646605 is an apocalyptic number.

It is an amenable number.

2005646605 is a deficient number, since it is larger than the sum of its proper divisors (490787867).

2005646605 is a wasteful number, since it uses less digits than its factorization.

2005646605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2785 (or 2748 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 34.

The square root of 2005646605 is about 44784.4460164464. The cubic root of 2005646605 is about 1261.1056485166.

The spelling of 2005646605 in words is "two billion, five million, six hundred forty-six thousand, six hundred five".