221022212021 has 4 divisors (see below), whose sum is σ = 238023920652. Its totient is φ = 204020503392.

The previous prime is 221022212017. The next prime is 221022212051. The reversal of 221022212021 is 120212220122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 79051507921 + 141970704100 = 281161^2 + 376790^2 .

It is a cyclic number.

It is not a de Polignac number, because 221022212021 - 2² = 221022212017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221022212051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8500854296 + ... + 8500854321.

It is an arithmetic number, because the mean of its divisors is an integer number (59505980163).

Almost surely, 2^221022212021 is an apocalyptic number.

It is an amenable number.

221022212021 is a deficient number, since it is larger than the sum of its proper divisors (17001708631).

221022212021 is a wasteful number, since it uses less digits than its factorization.

221022212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17001708630.

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

Adding to 221022212021 its reverse (120212220122), we get a palindrome (341234432143).

The spelling of 221022212021 in words is "two hundred twenty-one billion, twenty-two million, two hundred twelve thousand, twenty-one".