21102200020 has 24 divisors (see below), whose sum is σ = 48343222368. Its totient is φ = 7673527200.

The previous prime is 21102200017. The next prime is 21102200027. The reversal of 21102200020 is 2000220112.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102200027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47959326 + ... + 47959765.

It is an arithmetic number, because the mean of its divisors is an integer number (2014300932).

Almost surely, 2^21102200020 is an apocalyptic number.

21102200020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21102200020 is an abundant number, since it is smaller than the sum of its proper divisors (27241022348).

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

21102200020 is a wasteful number, since it uses less digits than its factorization.

21102200020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95919111 (or 95919109 counting only the distinct ones).

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

Adding to 21102200020 its reverse (2000220112), we get a palindrome (23102420132).

It can be divided in two parts, 21102 and 200020, that added together give a palindrome (221122).

The spelling of 21102200020 in words is "twenty-one billion, one hundred two million, two hundred thousand, twenty".