21021210100120 has 16 divisors (see below), whose sum is σ = 47297722725360. Its totient is φ = 8408484040032.

The previous prime is 21021210100109. The next prime is 21021210100141. The reversal of 21021210100120 is 2100101212012.

It is a self number, because there is not a number n which added to its sum of digits gives 21021210100120.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262765126212 + ... + 262765126291.

It is an arithmetic number, because the mean of its divisors is an integer number (2956107670335).

Almost surely, 2^{21021210100120} is an apocalyptic number.

21021210100120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021210100120 is an abundant number, since it is smaller than the sum of its proper divisors (26276512625240).

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

21021210100120 is a wasteful number, since it uses less digits than its factorization.

21021210100120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525530252514 (or 525530252510 counting only the distinct ones).

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

Adding to 21021210100120 its reverse (2100101212012), we get a palindrome (23121311312132).

The spelling of 21021210100120 in words is "twenty-one trillion, twenty-one billion, two hundred ten million, one hundred thousand, one hundred twenty".