201221011002191 has 2 divisors, whose sum is σ = 201221011002192. Its totient is φ = 201221011002190.

The previous prime is 201221011002107. The next prime is 201221011002203. The reversal of 201221011002191 is 191200110122102.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201221011002191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201221011002391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100610505501095 + 100610505501096.

It is an arithmetic number, because the mean of its divisors is an integer number (100610505501096).

Almost surely, 2^{201221011002191} is an apocalyptic number.

201221011002191 is a deficient number, since it is larger than the sum of its proper divisors (1).

201221011002191 is an equidigital number, since it uses as much as digits as its factorization.

201221011002191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 23.

Adding to 201221011002191 its reverse (191200110122102), we get a palindrome (392421121124293).

The spelling of 201221011002191 in words is "two hundred one trillion, two hundred twenty-one billion, eleven million, two thousand, one hundred ninety-one".