265334640661 has 2 divisors, whose sum is σ = 265334640662. Its totient is φ = 265334640660.

The previous prime is 265334640647. The next prime is 265334640671. The reversal of 265334640661 is 166046433562.

265334640661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 202837640625 + 62497000036 = 450375^2 + 249994^2 .

It is a cyclic number.

It is not a de Polignac number, because 265334640661 - 2³³ = 256744706069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (265334640631) 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 as a sum of consecutive naturals, namely, 132667320330 + 132667320331.

It is an arithmetic number, because the mean of its divisors is an integer number (132667320331).

Almost surely, 2^265334640661 is an apocalyptic number.

It is an amenable number.

265334640661 is a deficient number, since it is larger than the sum of its proper divisors (1).

265334640661 is an equidigital number, since it uses as much as digits as its factorization.

265334640661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1866240, while the sum is 46.

The spelling of 265334640661 in words is "two hundred sixty-five billion, three hundred thirty-four million, six hundred forty thousand, six hundred sixty-one".