21212102200 has 48 divisors (see below), whose sum is σ = 51018777000. Its totient is φ = 8192257920.

The previous prime is 21212102161. The next prime is 21212102201. The reversal of 21212102200 is 220121212.

It is a happy number.

It is a super-3 number, since 3×21212102200³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212102201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1822830 + ... + 1834429.

Almost surely, 2^21212102200 is an apocalyptic number.

21212102200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212102200 is an abundant number, since it is smaller than the sum of its proper divisors (29806674800).

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

21212102200 is a wasteful number, since it uses less digits than its factorization.

21212102200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3657304 (or 3657295 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21212102200 its reverse (220121212), we get a palindrome (21432223412).

The spelling of 21212102200 in words is "twenty-one billion, two hundred twelve million, one hundred two thousand, two hundred".