20004405 has 16 divisors (see below), whose sum is σ = 32262144. Its totient is φ = 10584000.

The previous prime is 20004367. The next prime is 20004419. The reversal of 20004405 is 50440002.

It is not a de Polignac number, because 20004405 - 2¹³ = 19996213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3346 + ... + 7155.

It is an arithmetic number, because the mean of its divisors is an integer number (2016384).

Almost surely, 2^20004405 is an apocalyptic number.

It is an amenable number.

20004405 is a deficient number, since it is larger than the sum of its proper divisors (12257739).

20004405 is a wasteful number, since it uses less digits than its factorization.

20004405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10636.

The product of its (nonzero) digits is 160, while the sum is 15.

The square root of 20004405 is about 4472.6284218567. The cubic root of 20004405 is about 271.4616885459.

Adding to 20004405 its reverse (50440002), we get a palindrome (70444407).

The spelling of 20004405 in words is "twenty million, four thousand, four hundred five".