1205802111617 has 2 divisors, whose sum is σ = 1205802111618. Its totient is φ = 1205802111616.

The previous prime is 1205802111599. The next prime is 1205802111671. The reversal of 1205802111617 is 7161112085021.

Together with next prime (1205802111671) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1100073736336 + 105728375281 = 1048844^2 + 325159^2 .

It is a cyclic number.

It is not a de Polignac number, because 1205802111617 - 2²⁴ = 1205785334401 is a prime.

It is a super-2 number, since 2×1205802111617² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1205802111697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602901055808 + 602901055809.

It is an arithmetic number, because the mean of its divisors is an integer number (602901055809).

Almost surely, 2^{1205802111617} is an apocalyptic number.

It is an amenable number.

1205802111617 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205802111617 is an equidigital number, since it uses as much as digits as its factorization.

1205802111617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 35.

Adding to 1205802111617 its reverse (7161112085021), we get a palindrome (8366914196638).

The spelling of 1205802111617 in words is "one trillion, two hundred five billion, eight hundred two million, one hundred eleven thousand, six hundred seventeen".