685745931 has 16 divisors (see below), whose sum is σ = 986580000. Its totient is φ = 421175040.

The previous prime is 685745899. The next prime is 685745939. The reversal of 685745931 is 139547586.

It is not a de Polignac number, because 685745931 - 2⁵ = 685745899 is a prime.

It is a super-2 number, since 2×685745931² = 940494963766113522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (685745939) 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 in 15 ways as a sum of consecutive naturals, for example, 3445 + ... + 37193.

It is an arithmetic number, because the mean of its divisors is an integer number (61661250).

Almost surely, 2^685745931 is an apocalyptic number.

685745931 is a deficient number, since it is larger than the sum of its proper divisors (300834069).

685745931 is a wasteful number, since it uses less digits than its factorization.

685745931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34286.

The product of its digits is 907200, while the sum is 48.

The square root of 685745931 is about 26186.7510585028. The cubic root of 685745931 is about 881.8358415904.

The spelling of 685745931 in words is "six hundred eighty-five million, seven hundred forty-five thousand, nine hundred thirty-one".