2005021605 has 16 divisors (see below), whose sum is σ = 3218491584. Its totient is φ = 1065859200.

The previous prime is 2005021597. The next prime is 2005021631. The reversal of 2005021605 is 5061205002.

2005021605 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2005021605 - 2³ = 2005021597 is a prime.

It is a super-2 number, since 2×2005021605² = 8040223273033552050, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 213096 + ... + 222305.

It is an arithmetic number, because the mean of its divisors is an integer number (201155724).

Almost surely, 2^2005021605 is an apocalyptic number.

It is an amenable number.

2005021605 is a deficient number, since it is larger than the sum of its proper divisors (1213469979).

2005021605 is a wasteful number, since it uses less digits than its factorization.

2005021605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 435716.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 2005021605 is about 44777.4676036955. The cubic root of 2005021605 is about 1260.9746395750.

Adding to 2005021605 its reverse (5061205002), we get a palindrome (7066226607).

The spelling of 2005021605 in words is "two billion, five million, twenty-one thousand, six hundred five".