21200100220 has 36 divisors (see below), whose sum is σ = 48208282920. Its totient is φ = 7827728064.

The previous prime is 21200100217. The next prime is 21200100227. The reversal of 21200100220 is 2200100212.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21200100197 and 21200100206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200100227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3132730 + ... + 3139489.

It is an arithmetic number, because the mean of its divisors is an integer number (1339118970).

Almost surely, 2^21200100220 is an apocalyptic number.

21200100220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200100220 is an abundant number, since it is smaller than the sum of its proper divisors (27008182700).

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

21200100220 is a wasteful number, since it uses less digits than its factorization.

21200100220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6272254 (or 6272239 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21200100220 its reverse (2200100212), we get a palindrome (23400200432).

The spelling of 21200100220 in words is "twenty-one billion, two hundred million, one hundred thousand, two hundred twenty".