221222202021 has 12 divisors (see below), whose sum is σ = 328179483372. Its totient is φ = 143495482176.

The previous prime is 221222201971. The next prime is 221222202023. The reversal of 221222202021 is 120202222122.

221222202021 is a `hidden beast` number, since 221 + 22 + 220 + 202 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 211039172100 + 10183029921 = 459390^2 + 100911^2 .

It is not a de Polignac number, because 221222202021 - 2¹¹ = 221222199973 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221222201985 and 221222202003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221222202023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 332165136 + ... + 332165801.

It is an arithmetic number, because the mean of its divisors is an integer number (27348290281).

Almost surely, 2^221222202021 is an apocalyptic number.

It is an amenable number.

221222202021 is a deficient number, since it is larger than the sum of its proper divisors (106957281351).

221222202021 is a wasteful number, since it uses less digits than its factorization.

221222202021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 664330980 (or 664330977 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 221222202021 its reverse (120202222122), we get a palindrome (341424424143).

The spelling of 221222202021 in words is "two hundred twenty-one billion, two hundred twenty-two million, two hundred two thousand, twenty-one".