21212222200100 has 36 divisors (see below), whose sum is σ = 46040449970004. Its totient is φ = 8483058871680.

The previous prime is 21212222200073. The next prime is 21212222200121. The reversal of 21212222200100 is 100222221212.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 4984038390016 + 16228183810084 = 2232496^2 + 4028422^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22409087 + ... + 23336486.

Almost surely, 2^{21212222200100} is an apocalyptic number.

21212222200100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212222200100 is an abundant number, since it is smaller than the sum of its proper divisors (24828227769904).

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

21212222200100 is a wasteful number, since it uses less digits than its factorization.

21212222200100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45750224 (or 45750217 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21212222200100 its reverse (100222221212), we get a palindrome (21312444421312).

The spelling of 21212222200100 in words is "twenty-one trillion, two hundred twelve billion, two hundred twenty-two million, two hundred thousand, one hundred".