221122122121 has 8 divisors (see below), whose sum is σ = 221660144640. Its totient is φ = 220584256512.

The previous prime is 221122122097. The next prime is 221122122187. The reversal of 221122122121 is 121221221122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221122122121 - 2¹³ = 221122113929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221122182121) 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 7 ways as a sum of consecutive naturals, for example, 3082761 + ... + 3153673.

It is an arithmetic number, because the mean of its divisors is an integer number (27707518080).

Almost surely, 2^221122122121 is an apocalyptic number.

It is an amenable number.

221122122121 is a deficient number, since it is larger than the sum of its proper divisors (538022519).

221122122121 is an equidigital number, since it uses as much as digits as its factorization.

221122122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78455.

The product of its digits is 128, while the sum is 19.

Adding to 221122122121 its reverse (121221221122), we get a palindrome (342343343243).

Subtracting from 221122122121 its reverse (121221221122), we obtain a palindrome (99900900999).

The spelling of 221122122121 in words is "two hundred twenty-one billion, one hundred twenty-two million, one hundred twenty-two thousand, one hundred twenty-one".