21210100120221 has 16 divisors (see below), whose sum is σ = 29789248665600. Its totient is φ = 13386543515568.

The previous prime is 21210100120193. The next prime is 21210100120327. The reversal of 21210100120221 is 12202100101212.

It is not a de Polignac number, because 21210100120221 - 2¹¹ = 21210100118173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21210100120221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210100124221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129211591 + ... + 129375636.

It is an arithmetic number, because the mean of its divisors is an integer number (1861828041600).

Almost surely, 2^{21210100120221} is an apocalyptic number.

It is an amenable number.

21210100120221 is a deficient number, since it is larger than the sum of its proper divisors (8579148545379).

21210100120221 is a wasteful number, since it uses less digits than its factorization.

21210100120221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258588688.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21210100120221 its reverse (12202100101212), we get a palindrome (33412200221433).

The spelling of 21210100120221 in words is "twenty-one trillion, two hundred ten billion, one hundred million, one hundred twenty thousand, two hundred twenty-one".