212121221000 has 64 divisors (see below), whose sum is σ = 534545509680. Its totient is φ = 78321676800.

The previous prime is 212121220957. The next prime is 212121221003. The reversal of 212121221000 is 122121212.

212121221000 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 8 ways, for example, as 3865156 + 212117355844 = 1966^2 + 460562^2 .

It is not an unprimeable number, because it can be changed into a prime (212121221003) 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 15 ways as a sum of consecutive naturals, for example, 8145509 + ... + 8171508.

Almost surely, 2^212121221000 is an apocalyptic number.

212121221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121221000 is an abundant number, since it is smaller than the sum of its proper divisors (322424288680).

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

212121221000 is a wasteful number, since it uses less digits than its factorization.

212121221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16317051 (or 16317037 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 212121221000 its reverse (122121212), we get a palindrome (212243342212).

The spelling of 212121221000 in words is "two hundred twelve billion, one hundred twenty-one million, two hundred twenty-one thousand".