21121100122222 has 64 divisors (see below), whose sum is σ = 34598808115200. Its totient is φ = 9631851989760.

The previous prime is 21121100122099. The next prime is 21121100122223. The reversal of 21121100122222 is 22222100112112.

It is a super-2 number, since 2×21121100122222² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a self number, because there is not a number n which added to its sum of digits gives 21121100122222.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121100122223) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 610295643 + ... + 610330249.

It is an arithmetic number, because the mean of its divisors is an integer number (540606376800).

Almost surely, 2^{21121100122222} is an apocalyptic number.

21121100122222 is a deficient number, since it is larger than the sum of its proper divisors (13477707992978).

21121100122222 is a wasteful number, since it uses less digits than its factorization.

21121100122222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36241.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21121100122222 its reverse (22222100112112), we get a palindrome (43343200234334).

The spelling of 21121100122222 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred million, one hundred twenty-two thousand, two hundred twenty-two".