685575161 has 2 divisors, whose sum is σ = 685575162. Its totient is φ = 685575160.

The previous prime is 685575151. The next prime is 685575203. The reversal of 685575161 is 161575586.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 343879936 + 341695225 = 18544^2 + 18485^2 .

It is a cyclic number.

It is not a de Polignac number, because 685575161 - 2⁶ = 685575097 is a prime.

It is not a weakly prime, because it can be changed into another prime (685575131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342787580 + 342787581.

It is an arithmetic number, because the mean of its divisors is an integer number (342787581).

Almost surely, 2^685575161 is an apocalyptic number.

It is an amenable number.

685575161 is a deficient number, since it is larger than the sum of its proper divisors (1).

685575161 is an equidigital number, since it uses as much as digits as its factorization.

685575161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252000, while the sum is 44.

The square root of 685575161 is about 26183.4902371704. The cubic root of 685575161 is about 881.7626348812.

The spelling of 685575161 in words is "six hundred eighty-five million, five hundred seventy-five thousand, one hundred sixty-one".