685709747 has 2 divisors, whose sum is σ = 685709748. Its totient is φ = 685709746.

The previous prime is 685709719. The next prime is 685709767. The reversal of 685709747 is 747907586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685709747 - 2⁶ = 685709683 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (685709767) 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, 342854873 + 342854874.

It is an arithmetic number, because the mean of its divisors is an integer number (342854874).

Almost surely, 2^685709747 is an apocalyptic number.

685709747 is a deficient number, since it is larger than the sum of its proper divisors (1).

685709747 is an equidigital number, since it uses as much as digits as its factorization.

685709747 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2963520, while the sum is 53.

The square root of 685709747 is about 26186.0601656683. The cubic root of 685709747 is about 881.8203310308.

The spelling of 685709747 in words is "six hundred eighty-five million, seven hundred nine thousand, seven hundred forty-seven".