21222200101212 has 384 divisors, whose sum is σ = 64671120783360. Its totient is φ = 5946435072000.

The previous prime is 21222200101187. The next prime is 21222200101231. The reversal of 21222200101212 is 21210100222212.

It is a happy number.

21222200101212 is a `hidden beast` number, since 21 + 222 + 200 + 10 + 1 + 212 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1092735262 + ... + 1092754682.

It is an arithmetic number, because the mean of its divisors is an integer number (168414377040).

Almost surely, 2^{21222200101212} is an apocalyptic number.

21222200101212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21222200101212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32335560391680).

21222200101212 is an abundant number, since it is smaller than the sum of its proper divisors (43448920682148).

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

21222200101212 is a wasteful number, since it uses less digits than its factorization.

21222200101212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20410 (or 20402 counting only the distinct ones).

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

Adding to 21222200101212 its reverse (21210100222212), we get a palindrome (42432300323424).

The spelling of 21222200101212 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred million, one hundred one thousand, two hundred twelve".