261535122765583 has 2 divisors, whose sum is σ = 261535122765584. Its totient is φ = 261535122765582.

The previous prime is 261535122765569. The next prime is 261535122765589. The reversal of 261535122765583 is 385567221535162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261535122765583 - 2⁹ = 261535122765071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261535122765589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130767561382791 + 130767561382792.

It is an arithmetic number, because the mean of its divisors is an integer number (130767561382792).

Almost surely, 2^{261535122765583} is an apocalyptic number.

261535122765583 is a deficient number, since it is larger than the sum of its proper divisors (1).

261535122765583 is an equidigital number, since it uses as much as digits as its factorization.

261535122765583 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720000, while the sum is 61.

The spelling of 261535122765583 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 eighty-three".