664465657 has 2 divisors, whose sum is σ = 664465658. Its totient is φ = 664465656.

The previous prime is 664465597. The next prime is 664465691. The reversal of 664465657 is 756564466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 613998841 + 50466816 = 24779^2 + 7104^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664465657 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 664465657.

It is not a weakly prime, because it can be changed into another prime (664465057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332232828 + 332232829.

It is an arithmetic number, because the mean of its divisors is an integer number (332232829).

Almost surely, 2^664465657 is an apocalyptic number.

It is an amenable number.

664465657 is a deficient number, since it is larger than the sum of its proper divisors (1).

664465657 is an equidigital number, since it uses as much as digits as its factorization.

664465657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3628800, while the sum is 49.

The square root of 664465657 is about 25777.2313680116. The cubic root of 664465657 is about 872.6180252649.

The spelling of 664465657 in words is "six hundred sixty-four million, four hundred sixty-five thousand, six hundred fifty-seven".