222121200121 has 4 divisors (see below), whose sum is σ = 222122394612. Its totient is φ = 222120005632.

The previous prime is 222121200079. The next prime is 222121200137. The reversal of 222121200121 is 121002121222.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 40931359225 + 181189840896 = 202315^2 + 425664^2 .

It is a cyclic number.

It is not a de Polignac number, because 222121200121 - 2¹¹ = 222121198073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 222121200095 and 222121200104.

It is not an unprimeable number, because it can be changed into a prime (222121204121) 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 in 3 ways as a sum of consecutive naturals, for example, 251656 + ... + 712441.

It is an arithmetic number, because the mean of its divisors is an integer number (55530598653).

Almost surely, 2^222121200121 is an apocalyptic number.

It is an amenable number.

222121200121 is a deficient number, since it is larger than the sum of its proper divisors (1194491).

222121200121 is an equidigital number, since it uses as much as digits as its factorization.

222121200121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1194490.

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

Adding to 222121200121 its reverse (121002121222), we get a palindrome (343123321343).

The spelling of 222121200121 in words is "two hundred twenty-two billion, one hundred twenty-one million, two hundred thousand, one hundred twenty-one".