2210021121221 has 4 divisors (see below), whose sum is σ = 2210047941132. Its totient is φ = 2209994301312.

The previous prime is 2210021121167. The next prime is 2210021121227. The reversal of 2210021121221 is 1221211200122.

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 835121822500 + 1374899298721 = 913850^2 + 1172561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2210021121221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2210021121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2210021121227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13285970 + ... + 13451283.

It is an arithmetic number, because the mean of its divisors is an integer number (552511985283).

Almost surely, 2^{2210021121221} is an apocalyptic number.

It is an amenable number.

2210021121221 is a deficient number, since it is larger than the sum of its proper divisors (26819911).

2210021121221 is an equidigital number, since it uses as much as digits as its factorization.

2210021121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26819910.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 2210021121221 its reverse (1221211200122), we get a palindrome (3431232321343).

The spelling of 2210021121221 in words is "two trillion, two hundred ten billion, twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".