261535122765533 has 2 divisors, whose sum is σ = 261535122765534. Its totient is φ = 261535122765532.

The previous prime is 261535122765457. The next prime is 261535122765569. The reversal of 261535122765533 is 335567221535162.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 260617209311449 + 917913454084 = 16143643^2 + 958078^2 .

It is a cyclic number.

It is not a de Polignac number, because 261535122765533 - 2⁸ = 261535122765277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261535122765583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130767561382766 + 130767561382767.

It is an arithmetic number, because the mean of its divisors is an integer number (130767561382767).

Almost surely, 2^{261535122765533} is an apocalyptic number.

It is an amenable number.

261535122765533 is a deficient number, since it is larger than the sum of its proper divisors (1).

261535122765533 is an equidigital number, since it uses as much as digits as its factorization.

261535122765533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34020000, while the sum is 56.

The spelling of 261535122765533 in words is "two hundred sixty-one trillion, five hundred thirty-five billion, one hundred twenty-two million, seven hundred sixty-five thousand, five hundred thirty-three".