21212112200 has 48 divisors (see below), whose sum is σ = 49330176000. Its totient is φ = 8482777920.

The previous prime is 21212112199. The next prime is 21212112203. The reversal of 21212112200 is 221121212.

It is not an unprimeable number, because it can be changed into a prime (21212112203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1013441 + ... + 1034159.

It is an arithmetic number, because the mean of its divisors is an integer number (1027712000).

Almost surely, 2^21212112200 is an apocalyptic number.

21212112200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212112200 is an abundant number, since it is smaller than the sum of its proper divisors (28118063800).

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

21212112200 is a wasteful number, since it uses less digits than its factorization.

21212112200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25854 (or 25845 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21212112200 its reverse (221121212), we get a palindrome (21433233412).

The spelling of 21212112200 in words is "twenty-one billion, two hundred twelve million, one hundred twelve thousand, two hundred".