21200323220 has 12 divisors (see below), whose sum is σ = 44520678804. Its totient is φ = 8480129280.

The previous prime is 21200323187. The next prime is 21200323237. The reversal of 21200323220 is 2232300212.

It can be written as a sum of positive squares in 2 ways, for example, as 8265355396 + 12934967824 = 90914^2 + 113732^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530008061 + ... + 530008100.

It is an arithmetic number, because the mean of its divisors is an integer number (3710056567).

Almost surely, 2^21200323220 is an apocalyptic number.

21200323220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200323220 is an abundant number, since it is smaller than the sum of its proper divisors (23320355584).

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

21200323220 is a wasteful number, since it uses less digits than its factorization.

21200323220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060016170 (or 1060016168 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

Adding to 21200323220 its reverse (2232300212), we get a palindrome (23432623432).

The spelling of 21200323220 in words is "twenty-one billion, two hundred million, three hundred twenty-three thousand, two hundred twenty".