265640661324161 has 8 divisors (see below), whose sum is σ = 266034966295464. Its totient is φ = 265246362035200.

The previous prime is 265640661324151. The next prime is 265640661324197. The reversal of 265640661324161 is 161423166046562.

It can be written as a sum of positive squares in 4 ways, for example, as 231908552359936 + 33732108964225 = 15228544^2 + 5807935^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 265640661324161 - 2¹⁰ = 265640661323137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (265640661324151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97224431 + ... + 99919323.

It is an arithmetic number, because the mean of its divisors is an integer number (33254370786933).

Almost surely, 2^{265640661324161} is an apocalyptic number.

It is an amenable number.

265640661324161 is a deficient number, since it is larger than the sum of its proper divisors (394304971303).

265640661324161 is a wasteful number, since it uses less digits than its factorization.

265640661324161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2841171.

The product of its (nonzero) digits is 7464960, while the sum is 53.

The spelling of 265640661324161 in words is "two hundred sixty-five trillion, six hundred forty billion, six hundred sixty-one million, three hundred twenty-four thousand, one hundred sixty-one".