21222210121 has 48 divisors (see below), whose sum is σ = 26248199040. Its totient is φ = 17077966080.

The previous prime is 21222210089. The next prime is 21222210133. The reversal of 21222210121 is 12101222212.

It is a happy number.

It is not a de Polignac number, because 21222210121 - 2⁵ = 21222210089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222210095 and 21222210104.

It is not an unprimeable number, because it can be changed into a prime (21222210221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32800620 + ... + 32801266.

It is an arithmetic number, because the mean of its divisors is an integer number (546837480).

Almost surely, 2^21222210121 is an apocalyptic number.

It is an amenable number.

21222210121 is a deficient number, since it is larger than the sum of its proper divisors (5025988919).

21222210121 is a wasteful number, since it uses less digits than its factorization.

21222210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1294 (or 1287 counting only the distinct ones).

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

Adding to 21222210121 its reverse (12101222212), we get a palindrome (33323432333).

The spelling of 21222210121 in words is "twenty-one billion, two hundred twenty-two million, two hundred ten thousand, one hundred twenty-one".