221202012221 has 2 divisors, whose sum is σ = 221202012222. Its totient is φ = 221202012220.

The previous prime is 221202012181. The next prime is 221202012247. The reversal of 221202012221 is 122210202122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138868022500 + 82333989721 = 372650^2 + 286939^2 .

It is a cyclic number.

It is not a de Polignac number, because 221202012221 - 2³⁴ = 204022143037 is a prime.

It is a Sophie Germain prime.

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 221202012221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221202012721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110601006110 + 110601006111.

It is an arithmetic number, because the mean of its divisors is an integer number (110601006111).

Almost surely, 2^221202012221 is an apocalyptic number.

It is an amenable number.

221202012221 is a deficient number, since it is larger than the sum of its proper divisors (1).

221202012221 is an equidigital number, since it uses as much as digits as its factorization.

221202012221 is an evil number, because the sum of its binary digits is even.

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

Adding to 221202012221 its reverse (122210202122), we get a palindrome (343412214343).

The spelling of 221202012221 in words is "two hundred twenty-one billion, two hundred two million, twelve thousand, two hundred twenty-one".