212121121100 has 72 divisors (see below), whose sum is σ = 526696393440. Its totient is φ = 72639313920.

The previous prime is 212121121067. The next prime is 212121121111. The reversal of 212121121100 is 1121121212.

212121121100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 397532 + ... + 763068.

Almost surely, 2^212121121100 is an apocalyptic number.

212121121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212121121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263348196720).

212121121100 is an abundant number, since it is smaller than the sum of its proper divisors (314575272340).

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

212121121100 is a wasteful number, since it uses less digits than its factorization.

212121121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 366387 (or 366380 counting only the distinct ones).

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

Adding to 212121121100 its reverse (1121121212), we get a palindrome (213242242312).

The spelling of 212121121100 in words is "two hundred twelve billion, one hundred twenty-one million, one hundred twenty-one thousand, one hundred".