21221102100222 has 192 divisors, whose sum is σ = 50284985587200. Its totient is φ = 6444915206400.

The previous prime is 21221102100157. The next prime is 21221102100239. The reversal of 21221102100222 is 22200120112212.

It is a happy number.

21221102100222 is a `hidden beast` number, since 2 + 1 + 221 + 10 + 210 + 0 + 222 = 666.

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 = 21221102100195 and 21221102100204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 378237972 + ... + 378294072.

It is an arithmetic number, because the mean of its divisors is an integer number (261900966600).

Almost surely, 2^{21221102100222} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21221102100222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25142492793600).

21221102100222 is an abundant number, since it is smaller than the sum of its proper divisors (29063883486978).

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

21221102100222 is a wasteful number, since it uses less digits than its factorization.

21221102100222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56511 (or 56508 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21221102100222 its reverse (22200120112212), we get a palindrome (43421222212434).

The spelling of 21221102100222 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred two million, one hundred thousand, two hundred twenty-two".