2001220211171 has 2 divisors, whose sum is σ = 2001220211172. Its totient is φ = 2001220211170.

The previous prime is 2001220211063. The next prime is 2001220211227. The reversal of 2001220211171 is 1711120221002.

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-2001220211171 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001220213171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610105585 + 1000610105586.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610105586).

Almost surely, 2^{2001220211171} is an apocalyptic number.

2001220211171 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001220211171 is an equidigital number, since it uses as much as digits as its factorization.

2001220211171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 2001220211171 its reverse (1711120221002), we get a palindrome (3712340432173).

The spelling of 2001220211171 in words is "two trillion, one billion, two hundred twenty million, two hundred eleven thousand, one hundred seventy-one".