21210221200120 has 32 divisors (see below), whose sum is σ = 49797910645920. Its totient is φ = 8115215067520.

The previous prime is 21210221200117. The next prime is 21210221200169. The reversal of 21210221200120 is 2100212201212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21210221200094 and 21210221200103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11527293211 + ... + 11527295050.

It is an arithmetic number, because the mean of its divisors is an integer number (1556184707685).

Almost surely, 2^{21210221200120} is an apocalyptic number.

21210221200120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210221200120 is an abundant number, since it is smaller than the sum of its proper divisors (28587689445800).

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

21210221200120 is a wasteful number, since it uses less digits than its factorization.

21210221200120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23054588295 (or 23054588291 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21210221200120 its reverse (2100212201212), we get a palindrome (23310433401332).

The spelling of 21210221200120 in words is "twenty-one trillion, two hundred ten billion, two hundred twenty-one million, two hundred thousand, one hundred twenty".