21221201022120 has 192 divisors, whose sum is σ = 76988543860800. Its totient is φ = 5024893224960.

The previous prime is 21221201022089. The next prime is 21221201022169. The reversal of 21221201022120 is 2122010212212.

It is a happy number.

21221201022120 is a `hidden beast` number, since 2 + 1 + 221 + 201 + 0 + 221 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21221201022093 and 21221201022102.

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 47 ways as a sum of consecutive naturals, for example, 62142385 + ... + 62482944.

It is an arithmetic number, because the mean of its divisors is an integer number (400981999275).

Almost surely, 2^{21221201022120} is an apocalyptic number.

21221201022120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221201022120 is an abundant number, since it is smaller than the sum of its proper divisors (55767342838680).

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

21221201022120 is a wasteful number, since it uses less digits than its factorization.

21221201022120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124625400 (or 124625393 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21221201022120 its reverse (2122010212212), we get a palindrome (23343211234332).

The spelling of 21221201022120 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred one million, twenty-two thousand, one hundred twenty".