20005505 has 16 divisors (see below), whose sum is σ = 26747280. Its totient is φ = 14262528.

The previous prime is 20005501. The next prime is 20005507. The reversal of 20005505 is 50550002.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 283024 + 19722481 = 532^2 + 4441^2 .

It is a cyclic number.

It is not a de Polignac number, because 20005505 - 2² = 20005501 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20005501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3422 + ... + 7191.

It is an arithmetic number, because the mean of its divisors is an integer number (1671705).

Almost surely, 2^20005505 is an apocalyptic number.

It is an amenable number.

20005505 is a deficient number, since it is larger than the sum of its proper divisors (6741775).

20005505 is a wasteful number, since it uses less digits than its factorization.

20005505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10660.

The product of its (nonzero) digits is 250, while the sum is 17.

The square root of 20005505 is about 4472.7513903637. The cubic root of 20005505 is about 271.4666641565.

Adding to 20005505 its reverse (50550002), we get a palindrome (70555507).

The spelling of 20005505 in words is "twenty million, five thousand, five hundred five".