21212222422 has 16 divisors (see below), whose sum is σ = 32069652912. Its totient is φ = 10522380960.

The previous prime is 21212222363. The next prime is 21212222431. The reversal of 21212222422 is 22422221212.

It is a junction number, because it is equal to n+sod(n) for n = 21212222393 and 21212222402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1290568 + ... + 1306900.

It is an arithmetic number, because the mean of its divisors is an integer number (2004353307).

Almost surely, 2^21212222422 is an apocalyptic number.

21212222422 is a deficient number, since it is larger than the sum of its proper divisors (10857430490).

21212222422 is a wasteful number, since it uses less digits than its factorization.

21212222422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21423.

The product of its digits is 1024, while the sum is 22.

Adding to 21212222422 its reverse (22422221212), we get a palindrome (43634443634).

The spelling of 21212222422 in words is "twenty-one billion, two hundred twelve million, two hundred twenty-two thousand, four hundred twenty-two".