268661609 has 2 divisors, whose sum is σ = 268661610. Its totient is φ = 268661608.

The previous prime is 268661587. The next prime is 268661623. The reversal of 268661609 is 906166862.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173501584 + 95160025 = 13172^2 + 9755^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-268661609 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 268661609.

It is not a weakly prime, because it can be changed into another prime (268661639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 134330804 + 134330805.

It is an arithmetic number, because the mean of its divisors is an integer number (134330805).

Almost surely, 2^268661609 is an apocalyptic number.

It is an amenable number.

268661609 is a deficient number, since it is larger than the sum of its proper divisors (1).

268661609 is an equidigital number, since it uses as much as digits as its factorization.

268661609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 268661609 is about 16390.9001888243. The cubic root of 268661609 is about 645.2606834427.

The spelling of 268661609 in words is "two hundred sixty-eight million, six hundred sixty-one thousand, six hundred nine".