21220012200 has 192 divisors, whose sum is σ = 67268640960. Its totient is φ = 5532088320.

The previous prime is 21220012183. The next prime is 21220012201. The reversal of 21220012200 is 221002212.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21220012201) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 5505474 + ... + 5509326.

It is an arithmetic number, because the mean of its divisors is an integer number (350357505).

Almost surely, 2^21220012200 is an apocalyptic number.

21220012200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220012200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33634320480).

21220012200 is an abundant number, since it is smaller than the sum of its proper divisors (46048628760).

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

21220012200 is a wasteful number, since it uses less digits than its factorization.

21220012200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4076 (or 4067 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21220012200 its reverse (221002212), we get a palindrome (21441014412).

The spelling of 21220012200 in words is "twenty-one billion, two hundred twenty million, twelve thousand, two hundred".