21100200020 has 12 divisors (see below), whose sum is σ = 44310420084. Its totient is φ = 8440080000.

The previous prime is 21100200019. The next prime is 21100200041. The reversal of 21100200020 is 2000200112.

It can be written as a sum of positive squares in 2 ways, for example, as 10169915716 + 10930284304 = 100846^2 + 104548^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21100199980 and 21100200007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 527504981 + ... + 527505020.

It is an arithmetic number, because the mean of its divisors is an integer number (3692535007).

Almost surely, 2^21100200020 is an apocalyptic number.

21100200020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100200020 is an abundant number, since it is smaller than the sum of its proper divisors (23210220064).

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

21100200020 is a wasteful number, since it uses less digits than its factorization.

21100200020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1055010010 (or 1055010008 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

Adding to 21100200020 its reverse (2000200112), we get a palindrome (23100400132).

The spelling of 21100200020 in words is "twenty-one billion, one hundred million, two hundred thousand, twenty".