665857477 has 2 divisors, whose sum is σ = 665857478. Its totient is φ = 665857476.

The previous prime is 665857459. The next prime is 665857483. The reversal of 665857477 is 774758566.

665857477 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 657871201 + 7986276 = 25649^2 + 2826^2 .

It is a cyclic number.

It is not a de Polignac number, because 665857477 - 2⁷ = 665857349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665857447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332928738 + 332928739.

It is an arithmetic number, because the mean of its divisors is an integer number (332928739).

Almost surely, 2^665857477 is an apocalyptic number.

It is an amenable number.

665857477 is a deficient number, since it is larger than the sum of its proper divisors (1).

665857477 is an equidigital number, since it uses as much as digits as its factorization.

665857477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9878400, while the sum is 55.

The square root of 665857477 is about 25804.2143263460. The cubic root of 665857477 is about 873.2268754948.

The spelling of 665857477 in words is "six hundred sixty-five million, eight hundred fifty-seven thousand, four hundred seventy-seven".