212121210100 has 18 divisors (see below), whose sum is σ = 460303026134. Its totient is φ = 84848484000.

The previous prime is 212121210053. The next prime is 212121210109. The reversal of 212121210100 is 1012121212.

212121210100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 169744 + 212121040356 = 412^2 + 460566^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121210109) 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 5 ways as a sum of consecutive naturals, for example, 1060605951 + ... + 1060606150.

Almost surely, 2^212121210100 is an apocalyptic number.

212121210100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121210100 is an abundant number, since it is smaller than the sum of its proper divisors (248181816034).

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

212121210100 is a wasteful number, since it uses less digits than its factorization.

212121210100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2121212115 (or 2121212108 counting only the distinct ones).

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

Adding to 212121210100 its reverse (1012121212), we get a palindrome (213133331312).

It can be divided in two parts, 2121212 and 10100, that added together give a palindrome (2131312).

The spelling of 212121210100 in words is "two hundred twelve billion, one hundred twenty-one million, two hundred ten thousand, one hundred".