21222102222 has 24 divisors (see below), whose sum is σ = 47684230776. Its totient is φ = 7074033912.

The previous prime is 21222102221. The next prime is 21222102229. The reversal of 21222102222 is 22220122212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21222102195 and 21222102204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222102221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21832953 + ... + 21833924.

It is an arithmetic number, because the mean of its divisors is an integer number (1986842949).

Almost surely, 2^21222102222 is an apocalyptic number.

21222102222 is an abundant number, since it is smaller than the sum of its proper divisors (26462128554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21222102222 is an equidigital number, since it uses as much as digits as its factorization.

21222102222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43666894 (or 43666882 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21222102222 its reverse (22220122212), we get a palindrome (43442224434).

The spelling of 21222102222 in words is "twenty-one billion, two hundred twenty-two million, one hundred two thousand, two hundred twenty-two".