685256930177 has 2 divisors, whose sum is σ = 685256930178. Its totient is φ = 685256930176.

The previous prime is 685256930159. The next prime is 685256930191. The reversal of 685256930177 is 771039652586.

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., 611509924081 + 73747006096 = 781991^2 + 271564^2 .

It is a cyclic number.

It is not a de Polignac number, because 685256930177 - 2²⁰ = 685255881601 is a prime.

It is not a weakly prime, because it can be changed into another prime (685256900177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342628465088 + 342628465089.

It is an arithmetic number, because the mean of its divisors is an integer number (342628465089).

Almost surely, 2^685256930177 is an apocalyptic number.

It is an amenable number.

685256930177 is a deficient number, since it is larger than the sum of its proper divisors (1).

685256930177 is an equidigital number, since it uses as much as digits as its factorization.

685256930177 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19051200, while the sum is 59.

The spelling of 685256930177 in words is "six hundred eighty-five billion, two hundred fifty-six million, nine hundred thirty thousand, one hundred seventy-seven".