665387017 has 2 divisors, whose sum is σ = 665387018. Its totient is φ = 665387016.

The previous prime is 665386999. The next prime is 665387077. The reversal of 665387017 is 710783566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 524822281 + 140564736 = 22909^2 + 11856^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665387017 is a prime.

It is not a weakly prime, because it can be changed into another prime (665387077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332693508 + 332693509.

It is an arithmetic number, because the mean of its divisors is an integer number (332693509).

Almost surely, 2^665387017 is an apocalyptic number.

It is an amenable number.

665387017 is a deficient number, since it is larger than the sum of its proper divisors (1).

665387017 is an equidigital number, since it uses as much as digits as its factorization.

665387017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 211680, while the sum is 43.

The square root of 665387017 is about 25795.0967627571. The cubic root of 665387017 is about 873.0211682565.

The spelling of 665387017 in words is "six hundred sixty-five million, three hundred eighty-seven thousand, seventeen".