685683971 has 4 divisors (see below), whose sum is σ = 783638832. Its totient is φ = 587729112.

The previous prime is 685683931. The next prime is 685683983. The reversal of 685683971 is 179386586.

It is a happy number.

685683971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 179386586 = 2 ⋅89693293.

It is a cyclic number.

It is not a de Polignac number, because 685683971 - 2⁶ = 685683907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685683931) 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, 48977420 + ... + 48977433.

It is an arithmetic number, because the mean of its divisors is an integer number (195909708).

Almost surely, 2^685683971 is an apocalyptic number.

685683971 is a deficient number, since it is larger than the sum of its proper divisors (97954861).

685683971 is an equidigital number, since it uses as much as digits as its factorization.

685683971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97954860.

The product of its digits is 2177280, while the sum is 53.

The square root of 685683971 is about 26185.5679907845. The cubic root of 685683971 is about 881.8092816105.

The spelling of 685683971 in words is "six hundred eighty-five million, six hundred eighty-three thousand, nine hundred seventy-one".