21200220009 has 6 divisors (see below), whose sum is σ = 30622540026. Its totient is φ = 14133480000.

The previous prime is 21200219987. The next prime is 21200220049. The reversal of 21200220009 is 90002200212.

It can be written as a sum of positive squares in only one way, i.e., 15485313600 + 5714906409 = 124440^2 + 75597^2 .

It is not a de Polignac number, because 21200220009 - 2⁷ = 21200219881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21200219973 and 21200220000.

It is not an unprimeable number, because it can be changed into a prime (21200220049) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1177789992 + ... + 1177790009.

It is an arithmetic number, because the mean of its divisors is an integer number (5103756671).

Almost surely, 2^21200220009 is an apocalyptic number.

It is an amenable number.

21200220009 is a deficient number, since it is larger than the sum of its proper divisors (9422320017).

21200220009 is a wasteful number, since it uses less digits than its factorization.

21200220009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2355580007 (or 2355580004 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The spelling of 21200220009 in words is "twenty-one billion, two hundred million, two hundred twenty thousand, nine".