21011200212 has 144 divisors (see below), whose sum is σ = 54315225216. Its totient is φ = 6304953600.

The previous prime is 21011200207. The next prime is 21011200213. The reversal of 21011200212 is 21200211012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011200213) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9812662 + ... + 9814802.

It is an arithmetic number, because the mean of its divisors is an integer number (377189064).

Almost surely, 2^21011200212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21011200212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27157612608).

21011200212 is an abundant number, since it is smaller than the sum of its proper divisors (33304025004).

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

21011200212 is a wasteful number, since it uses less digits than its factorization.

21011200212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2270 (or 2237 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21011200212 its reverse (21200211012), we get a palindrome (42211411224).

The spelling of 21011200212 in words is "twenty-one billion, eleven million, two hundred thousand, two hundred twelve".