21200022209 has 8 divisors (see below), whose sum is σ = 21228275880. Its totient is φ = 21171790336.

The previous prime is 21200022197. The next prime is 21200022211. The reversal of 21200022209 is 90222000212.

It can be written as a sum of positive squares in 4 ways, for example, as 12166090000 + 9033932209 = 110300^2 + 95047^2 .

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-21200022209 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 (21200028209) 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, 2816519 + ... + 2824035.

It is an arithmetic number, because the mean of its divisors is an integer number (2653534485).

Almost surely, 2^21200022209 is an apocalyptic number.

It is an amenable number.

21200022209 is a deficient number, since it is larger than the sum of its proper divisors (28253671).

21200022209 is a wasteful number, since it uses less digits than its factorization.

21200022209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10899.

The product of its (nonzero) digits is 288, while the sum is 20.

The spelling of 21200022209 in words is "twenty-one billion, two hundred million, twenty-two thousand, two hundred nine".