210120212221 has 4 divisors (see below), whose sum is σ = 212047920700. Its totient is φ = 208192503744.

The previous prime is 210120212219. The next prime is 210120212227. The reversal of 210120212221 is 122212021012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 129924202500 + 80196009721 = 360450^2 + 283189^2 .

It is a cyclic number.

It is not a de Polignac number, because 210120212221 - 2¹ = 210120212219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210120212195 and 210120212204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210120212227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 963854076 + ... + 963854293.

It is an arithmetic number, because the mean of its divisors is an integer number (53011980175).

Almost surely, 2^210120212221 is an apocalyptic number.

It is an amenable number.

210120212221 is a deficient number, since it is larger than the sum of its proper divisors (1927708479).

210120212221 is a wasteful number, since it uses less digits than its factorization.

210120212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1927708478.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 210120212221 its reverse (122212021012), we get a palindrome (332332233233).

The spelling of 210120212221 in words is "two hundred ten billion, one hundred twenty million, two hundred twelve thousand, two hundred twenty-one".