21200100210 has 48 divisors (see below), whose sum is σ = 55211210496. Its totient is φ = 5644031904.

The previous prime is 21200100161. The next prime is 21200100211. The reversal of 21200100210 is 1200100212.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21200100192 and 21200100201.

It is not an unprimeable number, because it can be changed into a prime (21200100211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 139404 + ... + 248663.

It is an arithmetic number, because the mean of its divisors is an integer number (1150233552).

Almost surely, 2^21200100210 is an apocalyptic number.

21200100210 is an abundant number, since it is smaller than the sum of its proper divisors (34011110286).

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

21200100210 is a wasteful number, since it uses less digits than its factorization.

21200100210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388687 (or 388684 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21200100210 its reverse (1200100212), we get a palindrome (22400200422).

The spelling of 21200100210 in words is "twenty-one billion, two hundred million, one hundred thousand, two hundred ten".