221201000202221 has 4 divisors (see below), whose sum is σ = 238216461756252. Its totient is φ = 204185538648192.

The previous prime is 221201000202197. The next prime is 221201000202251. The reversal of 221201000202221 is 122202000102122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 140093594620996 + 81107405581225 = 11836114^2 + 9005965^2 .

It is a cyclic number.

It is not a de Polignac number, because 221201000202221 - 2⁴² = 216802953691117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221201000202221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221201000202251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8507730776996 + ... + 8507730777021.

It is an arithmetic number, because the mean of its divisors is an integer number (59554115439063).

Almost surely, 2^{221201000202221} is an apocalyptic number.

It is an amenable number.

221201000202221 is a deficient number, since it is larger than the sum of its proper divisors (17015461554031).

221201000202221 is a wasteful number, since it uses less digits than its factorization.

221201000202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17015461554030.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 221201000202221 its reverse (122202000102122), we get a palindrome (343403000304343).

The spelling of 221201000202221 in words is "two hundred twenty-one trillion, two hundred one billion, two hundred two thousand, two hundred twenty-one".