21010120100221 has 24 divisors (see below), whose sum is σ = 24646791281280. Its totient is φ = 17857185091200.

The previous prime is 21010120100197. The next prime is 21010120100273. The reversal of 21010120100221 is 12200102101012.

It is not a de Polignac number, because 21010120100221 - 2⁴³ = 12214027078013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010120700221) 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, 947436 + ... + 6551173.

It is an arithmetic number, because the mean of its divisors is an integer number (1026949636720).

Almost surely, 2^{21010120100221} is an apocalyptic number.

It is an amenable number.

21010120100221 is a deficient number, since it is larger than the sum of its proper divisors (3636671181059).

21010120100221 is a wasteful number, since it uses less digits than its factorization.

21010120100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7499105 (or 7499098 counting only the distinct ones).

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

Adding to 21010120100221 its reverse (12200102101012), we get a palindrome (33210222201233).

The spelling of 21010120100221 in words is "twenty-one trillion, ten billion, one hundred twenty million, one hundred thousand, two hundred twenty-one".