665322257 has 2 divisors, whose sum is σ = 665322258. Its totient is φ = 665322256.

The previous prime is 665322233. The next prime is 665322269. The reversal of 665322257 is 752223566.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 581581456 + 83740801 = 24116^2 + 9151^2 .

It is a cyclic number.

It is not a de Polignac number, because 665322257 - 2¹⁶ = 665256721 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 665322257.

It is not a weakly prime, because it can be changed into another prime (665322277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332661128 + 332661129.

It is an arithmetic number, because the mean of its divisors is an integer number (332661129).

Almost surely, 2^665322257 is an apocalyptic number.

It is an amenable number.

665322257 is a deficient number, since it is larger than the sum of its proper divisors (1).

665322257 is an equidigital number, since it uses as much as digits as its factorization.

665322257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 151200, while the sum is 38.

The square root of 665322257 is about 25793.8414548900. The cubic root of 665322257 is about 872.9928445473.

The spelling of 665322257 in words is "six hundred sixty-five million, three hundred twenty-two thousand, two hundred fifty-seven".