21102122222 has 4 divisors (see below), whose sum is σ = 31653183336. Its totient is φ = 10551061110.

The previous prime is 21102122201. The next prime is 21102122227. The reversal of 21102122222 is 22222120112.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21102122222.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102122227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5275530554 + ... + 5275530557.

It is an arithmetic number, because the mean of its divisors is an integer number (7913295834).

Almost surely, 2^21102122222 is an apocalyptic number.

21102122222 is a deficient number, since it is larger than the sum of its proper divisors (10551061114).

21102122222 is a wasteful number, since it uses less digits than its factorization.

21102122222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10551061113.

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

Adding to 21102122222 its reverse (22222120112), we get a palindrome (43324242334).

The spelling of 21102122222 in words is "twenty-one billion, one hundred two million, one hundred twenty-two thousand, two hundred twenty-two".