21120212221020 has 192 divisors, whose sum is σ = 73993002209280. Its totient is φ = 4954888454400.

The previous prime is 21120212221019. The next prime is 21120212221057. The reversal of 21120212221020 is 2012221202112.

It is a happy number.

21120212221020 is a `hidden beast` number, since 211 + 2 + 0 + 212 + 221 + 0 + 20 = 666.

It is a super-2 number, since 2×21120212221020² (a number of 27 digits) contains 22 as substring.

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 = 21120212220984 and 21120212221002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 57164107 + ... + 57532386.

It is an arithmetic number, because the mean of its divisors is an integer number (385380219840).

Almost surely, 2^{21120212221020} is an apocalyptic number.

21120212221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120212221020 is an abundant number, since it is smaller than the sum of its proper divisors (52872789988260).

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

21120212221020 is a wasteful number, since it uses less digits than its factorization.

21120212221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114696553 (or 114696545 counting only the distinct ones).

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

Adding to 21120212221020 its reverse (2012221202112), we get a palindrome (23132433423132).

The spelling of 21120212221020 in words is "twenty-one trillion, one hundred twenty billion, two hundred twelve million, two hundred twenty-one thousand, twenty".