222121221021 has 24 divisors (see below), whose sum is σ = 379320314880. Its totient is φ = 122549638176.

The previous prime is 222121221019. The next prime is 222121221029. The reversal of 222121221021 is 120122121222.

It is a happy number.

222121221021 is a `hidden beast` number, since 2 + 221 + 212 + 210 + 21 = 666.

It is not a de Polignac number, because 222121221021 - 2¹ = 222121221019 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 222121220985 and 222121221003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121221029) 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, 60786685 + ... + 60790338.

It is an arithmetic number, because the mean of its divisors is an integer number (15805013120).

Almost surely, 2^222121221021 is an apocalyptic number.

222121221021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

222121221021 is a deficient number, since it is larger than the sum of its proper divisors (157199093859).

222121221021 is a wasteful number, since it uses less digits than its factorization.

222121221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121577065 (or 121577062 counting only the distinct ones).

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

Adding to 222121221021 its reverse (120122121222), we get a palindrome (342243342243).

The spelling of 222121221021 in words is "two hundred twenty-two billion, one hundred twenty-one million, two hundred twenty-one thousand, twenty-one".