21212111200100 has 36 divisors (see below), whose sum is σ = 46036590998244. Its totient is φ = 8483681402880.

The previous prime is 21212111200097. The next prime is 21212111200229. The reversal of 21212111200100 is 100211121212.

It can be written as a sum of positive squares in 6 ways, for example, as 4903000489984 + 16309110710116 = 2214272^2 + 4038454^2 .

It is an unprimeable number.

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, 13805117 + ... + 15264516.

Almost surely, 2^{21212111200100} is an apocalyptic number.

21212111200100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212111200100 is an abundant number, since it is smaller than the sum of its proper divisors (24824479798144).

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

21212111200100 is a wasteful number, since it uses less digits than its factorization.

21212111200100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29076944 (or 29076937 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21212111200100 its reverse (100211121212), we get a palindrome (21312322321312).

The spelling of 21212111200100 in words is "twenty-one trillion, two hundred twelve billion, one hundred eleven million, two hundred thousand, one hundred".