21204422009 has 8 divisors (see below), whose sum is σ = 22413840000. Its totient is φ = 20004343632.

The previous prime is 21204421991. The next prime is 21204422021. The reversal of 21204422009 is 90022440212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21204422009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21204422059) 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, 2330234 + ... + 2339315.

It is an arithmetic number, because the mean of its divisors is an integer number (2801730000).

Almost surely, 2^21204422009 is an apocalyptic number.

It is an amenable number.

21204422009 is a deficient number, since it is larger than the sum of its proper divisors (1209417991).

21204422009 is a wasteful number, since it uses less digits than its factorization.

21204422009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4669807.

The product of its (nonzero) digits is 2304, while the sum is 26.

The spelling of 21204422009 in words is "twenty-one billion, two hundred four million, four hundred twenty-two thousand, nine".