201221100231101 has 2 divisors, whose sum is σ = 201221100231102. Its totient is φ = 201221100231100.

The previous prime is 201221100231089. The next prime is 201221100231103. The reversal of 201221100231101 is 101132001122102.

It is a happy number.

201221100231101 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200678417542201 + 542682688900 = 14166101^2 + 736670^2 .

It is a cyclic number.

It is not a de Polignac number, because 201221100231101 - 2¹⁸ = 201221099968957 is a prime.

Together with 201221100231103, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201221100231101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201221100231103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100610550115550 + 100610550115551.

It is an arithmetic number, because the mean of its divisors is an integer number (100610550115551).

Almost surely, 2^{201221100231101} is an apocalyptic number.

It is an amenable number.

201221100231101 is a deficient number, since it is larger than the sum of its proper divisors (1).

201221100231101 is an equidigital number, since it uses as much as digits as its factorization.

201221100231101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 201221100231101 its reverse (101132001122102), we get a palindrome (302353101353203).

The spelling of 201221100231101 in words is "two hundred one trillion, two hundred twenty-one billion, one hundred million, two hundred thirty-one thousand, one hundred one".