21021012101200 has 120 divisors (see below), whose sum is σ = 53483775803640. Its totient is φ = 7912308326400.

The previous prime is 21021012101039. The next prime is 21021012101207. The reversal of 21021012101200 is 210121012012.

21021012101200 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 12 ways, for example, as 6281279037504 + 14739733063696 = 2506248^2 + 3839236^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021012101207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36303556 + ... + 36878044.

It is an arithmetic number, because the mean of its divisors is an integer number (445698131697).

Almost surely, 2^{21021012101200} is an apocalyptic number.

21021012101200 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 21021012101200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26741887901820).

21021012101200 is an abundant number, since it is smaller than the sum of its proper divisors (32462763702440).

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

21021012101200 is a wasteful number, since it uses less digits than its factorization.

21021012101200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579905 (or 579894 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21021012101200 its reverse (210121012012), we get a palindrome (21231133113212).

The spelling of 21021012101200 in words is "twenty-one trillion, twenty-one billion, twelve million, one hundred one thousand, two hundred".