2001221201191 has 2 divisors, whose sum is σ = 2001221201192. Its totient is φ = 2001221201190.

The previous prime is 2001221201101. The next prime is 2001221201197. The reversal of 2001221201191 is 1911021221002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001221201191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221201197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610600595 + 1000610600596.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610600596).

Almost surely, 2^{2001221201191} is an apocalyptic number.

2001221201191 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221201191 is an equidigital number, since it uses as much as digits as its factorization.

2001221201191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 2001221201191 its reverse (1911021221002), we get a palindrome (3912242422193).

The spelling of 2001221201191 in words is "two trillion, one billion, two hundred twenty-one million, two hundred one thousand, one hundred ninety-one".