21122122222 has 16 divisors (see below), whose sum is σ = 31821833520. Its totient is φ = 10514884608.

The previous prime is 21122122193. The next prime is 21122122237. The reversal of 21122122222 is 22222122112.

It is a super-2 number, since 2×21122122222² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21122122222.

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 1197604 + ... + 1215112.

It is an arithmetic number, because the mean of its divisors is an integer number (1988864595).

Almost surely, 2^21122122222 is an apocalyptic number.

21122122222 is a deficient number, since it is larger than the sum of its proper divisors (10699711298).

21122122222 is a wasteful number, since it uses less digits than its factorization.

21122122222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20115.

The product of its digits is 256, while the sum is 19.

Adding to 21122122222 its reverse (22222122112), we get a palindrome (43344244334).

The spelling of 21122122222 in words is "twenty-one billion, one hundred twenty-two million, one hundred twenty-two thousand, two hundred twenty-two".