21306003204 has 24 divisors (see below), whose sum is σ = 49778676640. Its totient is φ = 7092762624.

The previous prime is 21306003203. The next prime is 21306003211. The reversal of 21306003204 is 40230060312.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21306003203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1145194 + ... + 1163649.

Almost surely, 2^21306003204 is an apocalyptic number.

It is an amenable number.

21306003204 is an abundant number, since it is smaller than the sum of its proper divisors (28472673436).

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

21306003204 is a wasteful number, since it uses less digits than its factorization.

21306003204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2309619 (or 2309617 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21306003204 its reverse (40230060312), we get a palindrome (61536063516).

The spelling of 21306003204 in words is "twenty-one billion, three hundred six million, three thousand, two hundred four".