21012121100200 has 48 divisors (see below), whose sum is σ = 49135569971580. Its totient is φ = 8356265487360.

The previous prime is 21012121100177. The next prime is 21012121100207. The reversal of 21012121100200 is 200112121012.

It can be written as a sum of positive squares in 6 ways, for example, as 5947833237124 + 15064287863076 = 2438818^2 + 3881274^2 .

It is not an unprimeable number, because it can be changed into a prime (21012121100207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 303608769 + ... + 303677968.

Almost surely, 2^{21012121100200} is an apocalyptic number.

21012121100200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012121100200 is an abundant number, since it is smaller than the sum of its proper divisors (28123448871380).

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

21012121100200 is a wasteful number, since it uses less digits than its factorization.

21012121100200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 607286926 (or 607286917 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21012121100200 its reverse (200112121012), we get a palindrome (21212233221212).

The spelling of 21012121100200 in words is "twenty-one trillion, twelve billion, one hundred twenty-one million, one hundred thousand, two hundred".