20409204 has 12 divisors (see below), whose sum is σ = 47621504. Its totient is φ = 6803064.

The previous prime is 20409203. The next prime is 20409209. The reversal of 20409204 is 40290402.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20409203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850372 + ... + 850395.

Almost surely, 2^20409204 is an apocalyptic number.

It is an amenable number.

20409204 is an abundant number, since it is smaller than the sum of its proper divisors (27212300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20409204 is a wasteful number, since it uses less digits than its factorization.

20409204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1700774 (or 1700772 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 20409204 is about 4517.6547012803. The cubic root of 20409204 is about 273.2805284999.

Adding to 20409204 its reverse (40290402), we get a palindrome (60699606).

The spelling of 20409204 in words is "twenty million, four hundred nine thousand, two hundred four".