21021021000120 has 256 divisors, whose sum is σ = 64699816089600. Its totient is φ = 5461244825600.

The previous prime is 21021021000047. The next prime is 21021021000121. The reversal of 21021021000120 is 2100012012012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21021021000096 and 21021021000105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021021000121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1982922820 + ... + 1982933420.

It is an arithmetic number, because the mean of its divisors is an integer number (252733656600).

Almost surely, 2^{21021021000120} is an apocalyptic number.

21021021000120 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 21021021000120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32349908044800).

21021021000120 is an abundant number, since it is smaller than the sum of its proper divisors (43678795089480).

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

21021021000120 is a wasteful number, since it uses less digits than its factorization.

21021021000120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12238 (or 12234 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21021021000120 its reverse (2100012012012), we get a palindrome (23121033012132).

The spelling of 21021021000120 in words is "twenty-one trillion, twenty-one billion, twenty-one million, one hundred twenty", and thus it is an aban number.