665768267 has 2 divisors, whose sum is σ = 665768268. Its totient is φ = 665768266.

The previous prime is 665768239. The next prime is 665768273. The reversal of 665768267 is 762867566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665768267 - 2¹² = 665764171 is a prime.

It is not a weakly prime, because it can be changed into another prime (665768287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332884133 + 332884134.

It is an arithmetic number, because the mean of its divisors is an integer number (332884134).

Almost surely, 2^665768267 is an apocalyptic number.

665768267 is a deficient number, since it is larger than the sum of its proper divisors (1).

665768267 is an equidigital number, since it uses as much as digits as its factorization.

665768267 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5080320, while the sum is 53.

The square root of 665768267 is about 25802.4856748337. The cubic root of 665768267 is about 873.1878761336.

The spelling of 665768267 in words is "six hundred sixty-five million, seven hundred sixty-eight thousand, two hundred sixty-seven".