221122201021 has 2 divisors, whose sum is σ = 221122201022. Its totient is φ = 221122201020.

The previous prime is 221122201019. The next prime is 221122201063. The reversal of 221122201021 is 120102221122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185253628921 + 35868572100 = 430411^2 + 189390^2 .

It is a cyclic number.

It is not a de Polignac number, because 221122201021 - 2¹ = 221122201019 is a prime.

Together with 221122201019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 221122200986 and 221122201004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221122201121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110561100510 + 110561100511.

It is an arithmetic number, because the mean of its divisors is an integer number (110561100511).

Almost surely, 2^221122201021 is an apocalyptic number.

It is an amenable number.

221122201021 is a deficient number, since it is larger than the sum of its proper divisors (1).

221122201021 is an equidigital number, since it uses as much as digits as its factorization.

221122201021 is an odious number, because the sum of its binary digits is odd.

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

Adding to 221122201021 its reverse (120102221122), we get a palindrome (341224422143).

The spelling of 221122201021 in words is "two hundred twenty-one billion, one hundred twenty-two million, two hundred one thousand, twenty-one".