2102201222221 has 4 divisors (see below), whose sum is σ = 2102452179772. Its totient is φ = 2101950264672.

The previous prime is 2102201222203. The next prime is 2102201222237. The reversal of 2102201222221 is 1222221022012.

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 1408995114121 + 693206108100 = 1187011^2 + 832590^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102201222221 - 2⁹ = 2102201221709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2102201222321) 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, 125466210 + ... + 125482963.

It is an arithmetic number, because the mean of its divisors is an integer number (525613044943).

Almost surely, 2^{2102201222221} is an apocalyptic number.

It is an amenable number.

2102201222221 is a deficient number, since it is larger than the sum of its proper divisors (250957551).

2102201222221 is an equidigital number, since it uses as much as digits as its factorization.

2102201222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250957550.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 2102201222221 its reverse (1222221022012), we get a palindrome (3324422244233).

The spelling of 2102201222221 in words is "two trillion, one hundred two billion, two hundred one million, two hundred twenty-two thousand, two hundred twenty-one".