21021212222 has 8 divisors (see below), whose sum is σ = 31821101400. Its totient is φ = 10414178424.

The previous prime is 21021212221. The next prime is 21021212231. The reversal of 21021212222 is 22221212012.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21021212222.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021212221) 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, 48213572 + ... + 48214007.

It is an arithmetic number, because the mean of its divisors is an integer number (3977637675).

Almost surely, 2^21021212222 is an apocalyptic number.

21021212222 is a deficient number, since it is larger than the sum of its proper divisors (10799889178).

21021212222 is a wasteful number, since it uses less digits than its factorization.

21021212222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96427690.

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

Adding to 21021212222 its reverse (22221212012), we get a palindrome (43242424234).

The spelling of 21021212222 in words is "twenty-one billion, twenty-one million, two hundred twelve thousand, two hundred twenty-two".