685748773 has 2 divisors, whose sum is σ = 685748774. Its totient is φ = 685748772.

The previous prime is 685748759. The next prime is 685748803. The reversal of 685748773 is 377847586.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 635947524 + 49801249 = 25218^2 + 7057^2 .

It is a cyclic number.

It is not a de Polignac number, because 685748773 - 2¹³ = 685740581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685746773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342874386 + 342874387.

It is an arithmetic number, because the mean of its divisors is an integer number (342874387).

Almost surely, 2^685748773 is an apocalyptic number.

It is an amenable number.

685748773 is a deficient number, since it is larger than the sum of its proper divisors (1).

685748773 is an equidigital number, since it uses as much as digits as its factorization.

685748773 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7902720, while the sum is 55.

The square root of 685748773 is about 26186.8053225284. The cubic root of 685748773 is about 881.8370598132.

The spelling of 685748773 in words is "six hundred eighty-five million, seven hundred forty-eight thousand, seven hundred seventy-three".