222021220121 has 24 divisors (see below), whose sum is σ = 235865405160. Its totient is φ = 208931982336.

The previous prime is 222021220111. The next prime is 222021220171. The reversal of 222021220121 is 121022120222.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 28632362521 + 193388857600 = 169211^2 + 439760^2 .

It is not a de Polignac number, because 222021220121 - 2³⁴ = 204841350937 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 222021220121.

It is not an unprimeable number, because it can be changed into a prime (222021220111) 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, 15787325 + ... + 15801381.

It is an arithmetic number, because the mean of its divisors is an integer number (9827725215).

Almost surely, 2^222021220121 is an apocalyptic number.

It is an amenable number.

222021220121 is a deficient number, since it is larger than the sum of its proper divisors (13844185039).

222021220121 is a wasteful number, since it uses less digits than its factorization.

222021220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14585 (or 14562 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 222021220121 its reverse (121022120222), we get a palindrome (343043340343).

The spelling of 222021220121 in words is "two hundred twenty-two billion, twenty-one million, two hundred twenty thousand, one hundred twenty-one".