21221221220200 has 96 divisors (see below), whose sum is σ = 52247926186560. Its totient is φ = 7988206361600.

The previous prime is 21221221220189. The next prime is 21221221220203. The reversal of 21221221220200 is 202212212212.

It is not an unprimeable number, because it can be changed into a prime (21221221220203) 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, 28267695 + ... + 29008705.

It is an arithmetic number, because the mean of its divisors is an integer number (544249231110).

Almost surely, 2^{21221221220200} is an apocalyptic number.

21221221220200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221221220200 is an abundant number, since it is smaller than the sum of its proper divisors (31026704966360).

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

21221221220200 is a wasteful number, since it uses less digits than its factorization.

21221221220200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 749467 (or 749458 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21221221220200 its reverse (202212212212), we get a palindrome (21423433432412).

The spelling of 21221221220200 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred".