21112020201221 has 32 divisors (see below), whose sum is σ = 22815241384320. Its totient is φ = 19470195763200.

The previous prime is 21112020201191. The next prime is 21112020201277. The reversal of 21112020201221 is 12210202021112.

It is a cyclic number.

It is not a de Polignac number, because 21112020201221 - 2¹⁴ = 21112020184837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21112020201221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112020207221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 699962381 + ... + 699992541.

It is an arithmetic number, because the mean of its divisors is an integer number (712976293260).

Almost surely, 2^{21112020201221} is an apocalyptic number.

It is an amenable number.

21112020201221 is a deficient number, since it is larger than the sum of its proper divisors (1703221183099).

21112020201221 is a wasteful number, since it uses less digits than its factorization.

21112020201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32165.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21112020201221 its reverse (12210202021112), we get a palindrome (33322222222333).

The spelling of 21112020201221 in words is "twenty-one trillion, one hundred twelve billion, twenty million, two hundred one thousand, two hundred twenty-one".