21210020020120 has 16 divisors (see below), whose sum is σ = 47722545045360. Its totient is φ = 8484008008032.

The previous prime is 21210020020117. The next prime is 21210020020139. The reversal of 21210020020120 is 2102002001212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21210020020120.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 265125250212 + ... + 265125250291.

It is an arithmetic number, because the mean of its divisors is an integer number (2982659065335).

Almost surely, 2^{21210020020120} is an apocalyptic number.

21210020020120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210020020120 is an abundant number, since it is smaller than the sum of its proper divisors (26512525025240).

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

21210020020120 is a wasteful number, since it uses less digits than its factorization.

21210020020120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530250500514 (or 530250500510 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21210020020120 its reverse (2102002001212), we get a palindrome (23312022021332).

The spelling of 21210020020120 in words is "twenty-one trillion, two hundred ten billion, twenty million, twenty thousand, one hundred twenty".