221122221121021 has 6 divisors (see below), whose sum is σ = 243051697595966. Its totient is φ = 201020201019000.

The previous prime is 221122221121013. The next prime is 221122221121133. The reversal of 221122221121021 is 120121122221122.

It can be written as a sum of positive squares in only one way, i.e., 186515014702500 + 34607206418521 = 13657050^2 + 5882789^2 .

It is not a de Polignac number, because 221122221121021 - 2³ = 221122221121013 is a prime.

It is a super-3 number, since 3×221122221121021³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221122221120983 and 221122221121001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221122221151021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 913728186330 + ... + 913728186571.

Almost surely, 2^{221122221121021} is an apocalyptic number.

It is an amenable number.

221122221121021 is a deficient number, since it is larger than the sum of its proper divisors (21929476474945).

221122221121021 is a wasteful number, since it uses less digits than its factorization.

221122221121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1827456372923 (or 1827456372912 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 22.

Adding to 221122221121021 its reverse (120121122221122), we get a palindrome (341243343342143).

The spelling of 221122221121021 in words is "two hundred twenty-one trillion, one hundred twenty-two billion, two hundred twenty-one million, one hundred twenty-one thousand, twenty-one".