202221122121 has 24 divisors (see below), whose sum is σ = 300312319944. Its totient is φ = 131030265600.

The previous prime is 202221122119. The next prime is 202221122237. The reversal of 202221122121 is 121221122202.

It is a happy number.

202221122121 is a `hidden beast` number, since 202 + 221 + 1 + 221 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 26103249225 + 176117872896 = 161565^2 + 419664^2 .

It is not a de Polignac number, because 202221122121 - 2¹ = 202221122119 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 202221122094 and 202221122103.

It is not an unprimeable number, because it can be changed into a prime (202221122821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12030 + ... + 636071.

It is an arithmetic number, because the mean of its divisors is an integer number (12513013331).

Almost surely, 2^202221122121 is an apocalyptic number.

It is an amenable number.

202221122121 is a deficient number, since it is larger than the sum of its proper divisors (98091197823).

202221122121 is a wasteful number, since it uses less digits than its factorization.

202221122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649081 (or 649078 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 202221122121 its reverse (121221122202), we get a palindrome (323442244323).

The spelling of 202221122121 in words is "two hundred two billion, two hundred twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".