21121212012200 has 48 divisors (see below), whose sum is σ = 49779514098780. Its totient is φ = 8332752130560.

The previous prime is 21121212012193. The next prime is 21121212012203. The reversal of 21121212012200 is 221021212112.

It can be written as a sum of positive squares in 6 ways, for example, as 14769310003396 + 6351902008804 = 3843086^2 + 2520298^2 .

It is a super-2 number, since 2×21121212012200² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121212012203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 723314579 + ... + 723343778.

Almost surely, 2^{21121212012200} is an apocalyptic number.

21121212012200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121212012200 is an abundant number, since it is smaller than the sum of its proper divisors (28658302086580).

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

21121212012200 is a wasteful number, since it uses less digits than its factorization.

21121212012200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1446658446 (or 1446658437 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21121212012200 its reverse (221021212112), we get a palindrome (21342233224312).

The spelling of 21121212012200 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twelve million, twelve thousand, two hundred".