21200212212 has 24 divisors (see below), whose sum is σ = 50400506016. Its totient is φ = 6933402528.

The previous prime is 21200212199. The next prime is 21200212237. The reversal of 21200212212 is 21221200212.

21200212212 is a modest number, since divided by 212212 gives 21200 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 21200212191 and 21200212200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16666198 + ... + 16667469.

It is an arithmetic number, because the mean of its divisors is an integer number (2100021084).

Almost surely, 2^21200212212 is an apocalyptic number.

It is an amenable number.

21200212212 is an abundant number, since it is smaller than the sum of its proper divisors (29200293804).

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

21200212212 is a wasteful number, since it uses less digits than its factorization.

21200212212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33333727 (or 33333725 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21200212212 its reverse (21221200212), we get a palindrome (42421412424).

It can be divided in two parts, 21200212 and 212, that multiplied together give a palindrome (4494444944).

The spelling of 21200212212 in words is "twenty-one billion, two hundred million, two hundred twelve thousand, two hundred twelve".