685971844 has 12 divisors (see below), whose sum is σ = 1239175168. Its totient is φ = 331921800.

The previous prime is 685971841. The next prime is 685971851. The reversal of 685971844 is 448179586.

It is a junction number, because it is equal to n+sod(n) for n = 685971791 and 685971800.

It is not an unprimeable number, because it can be changed into a prime (685971841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2765892 + ... + 2766139.

Almost surely, 2^685971844 is an apocalyptic number.

It is an amenable number.

685971844 is a deficient number, since it is larger than the sum of its proper divisors (553203324).

685971844 is a wasteful number, since it uses less digits than its factorization.

685971844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5532066 (or 5532064 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 52.

The square root of 685971844 is about 26191.0642013646. The cubic root of 685971844 is about 881.9326686603.

The spelling of 685971844 in words is "six hundred eighty-five million, nine hundred seventy-one thousand, eight hundred forty-four".