21200210020 has 48 divisors (see below), whose sum is σ = 49697258688. Its totient is φ = 7529880960.

The previous prime is 21200209993. The next prime is 21200210029. The reversal of 21200210020 is 2001200212.

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 = 21200209979 and 21200210006.

It is not an unprimeable number, because it can be changed into a prime (21200210029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1111059 + ... + 1129978.

It is an arithmetic number, because the mean of its divisors is an integer number (1035359556).

Almost surely, 2^21200210020 is an apocalyptic number.

21200210020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200210020 is an abundant number, since it is smaller than the sum of its proper divisors (28497048668).

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

21200210020 is a wasteful number, since it uses less digits than its factorization.

21200210020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2241100 (or 2241098 counting only the distinct ones).

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

Adding to 21200210020 its reverse (2001200212), we get a palindrome (23201410232).

The spelling of 21200210020 in words is "twenty-one billion, two hundred million, two hundred ten thousand, twenty".