2005755565009 has 21 divisors (see below), whose sum is σ = 2340612189147. Its totient is φ = 1718802679104.

The previous prime is 2005755565001. The next prime is 2005755565013. The reversal of 2005755565009 is 9005655575002.

The square root of 2005755565009 is 1416247.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1109552542609 + 896203022400 = 1053353^2 + 946680^2 .

It is not a de Polignac number, because 2005755565009 - 2³ = 2005755565001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2005755565001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 485770657 + ... + 485774785.

Almost surely, 2^{2005755565009} is an apocalyptic number.

2005755565009 is the 1416247-th square number.

2005755565009 is the 708124-th centered octagonal number.

It is an amenable number.

2005755565009 is a deficient number, since it is larger than the sum of its proper divisors (334856624138).

2005755565009 is an frugal number, since it uses more digits than its factorization.

2005755565009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8300 (or 4136 counting only the distinct ones).

The product of its (nonzero) digits is 2362500, while the sum is 49.

Multiplying 2005755565009 by its sum of digits (49), we get a square (98282022685441 = 9913729²).

2005755565009 divided by its sum of digits (49) gives a square (40933787041 = 202321²).

The spelling of 2005755565009 in words is "two trillion, five billion, seven hundred fifty-five million, five hundred sixty-five thousand, nine".