21212110102120 has 128 divisors (see below), whose sum is σ = 57423454156800. Its totient is φ = 6889082593536.

The previous prime is 21212110102091. The next prime is 21212110102163. The reversal of 21212110102120 is 2120101121212.

It is a super-3 number, since 3×21212110102120³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 21212110102094 and 21212110102103.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42776319 + ... + 43269361.

It is an arithmetic number, because the mean of its divisors is an integer number (448620735600).

Almost surely, 2^{21212110102120} is an apocalyptic number.

21212110102120 is a gapful number since it is divisible by the number (20) 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 21212110102120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28711727078400).

21212110102120 is an abundant number, since it is smaller than the sum of its proper divisors (36211344054680).

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

21212110102120 is a wasteful number, since it uses less digits than its factorization.

21212110102120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501167 (or 501163 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21212110102120 its reverse (2120101121212), we get a palindrome (23332211223332).

The spelling of 21212110102120 in words is "twenty-one trillion, two hundred twelve billion, one hundred ten million, one hundred two thousand, one hundred twenty".