261535060773209 has 2 divisors, whose sum is σ = 261535060773210. Its totient is φ = 261535060773208.

The previous prime is 261535060773187. The next prime is 261535060773271. The reversal of 261535060773209 is 902377060535162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 260209806240400 + 1325254532809 = 16131020^2 + 1151197^2 .

It is a cyclic number.

It is not a de Polignac number, because 261535060773209 - 2¹⁶ = 261535060707673 is a prime.

It is a super-2 number, since 2×261535060773209² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261535060773289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130767530386604 + 130767530386605.

It is an arithmetic number, because the mean of its divisors is an integer number (130767530386605).

Almost surely, 2^{261535060773209} is an apocalyptic number.

It is an amenable number.

261535060773209 is a deficient number, since it is larger than the sum of its proper divisors (1).

261535060773209 is an equidigital number, since it uses as much as digits as its factorization.

261535060773209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14288400, while the sum is 56.

The spelling of 261535060773209 in words is "two hundred sixty-one trillion, five hundred thirty-five billion, sixty million, seven hundred seventy-three thousand, two hundred nine".