665464601 has 2 divisors, whose sum is σ = 665464602. Its totient is φ = 665464600.

The previous prime is 665464567. The next prime is 665464649. The reversal of 665464601 is 106464566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 470890000 + 194574601 = 21700^2 + 13949^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665464601 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (665464651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332732300 + 332732301.

It is an arithmetic number, because the mean of its divisors is an integer number (332732301).

Almost surely, 2^665464601 is an apocalyptic number.

It is an amenable number.

665464601 is a deficient number, since it is larger than the sum of its proper divisors (1).

665464601 is an equidigital number, since it uses as much as digits as its factorization.

665464601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 38.

The square root of 665464601 is about 25796.6005706178. The cubic root of 665464601 is about 873.0550983053.

The spelling of 665464601 in words is "six hundred sixty-five million, four hundred sixty-four thousand, six hundred one".