211261344817 has 2 divisors, whose sum is σ = 211261344818. Its totient is φ = 211261344816.

The previous prime is 211261344787. The next prime is 211261344841. The reversal of 211261344817 is 718443162112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 186175853361 + 25085491456 = 431481^2 + 158384^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211261344817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211261344817.

It is not a weakly prime, because it can be changed into another prime (211261344887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105630672408 + 105630672409.

It is an arithmetic number, because the mean of its divisors is an integer number (105630672409).

Almost surely, 2^211261344817 is an apocalyptic number.

It is an amenable number.

211261344817 is a deficient number, since it is larger than the sum of its proper divisors (1).

211261344817 is an equidigital number, since it uses as much as digits as its factorization.

211261344817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 40.

The spelling of 211261344817 in words is "two hundred eleven billion, two hundred sixty-one million, three hundred forty-four thousand, eight hundred seventeen".