685808648217 has 24 divisors (see below), whose sum is σ = 1235049341760. Its totient is φ = 356264232480.

The previous prime is 685808648207. The next prime is 685808648219. The reversal of 685808648217 is 712846808586.

685808648217 is a `hidden beast` number, since 6 + 8 + 580 + 8 + 6 + 48 + 2 + 1 + 7 = 666.

It is not a de Polignac number, because 685808648217 - 2⁴ = 685808648201 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (685808648219) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 494810742 + ... + 494812127.

It is an arithmetic number, because the mean of its divisors is an integer number (51460389240).

Almost surely, 2^685808648217 is an apocalyptic number.

It is an amenable number.

685808648217 is a deficient number, since it is larger than the sum of its proper divisors (549240693543).

685808648217 is a wasteful number, since it uses less digits than its factorization.

685808648217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989622893 (or 989622890 counting only the distinct ones).

The product of its (nonzero) digits is 41287680, while the sum is 63.

It can be divided in two parts, 685808 and 648217, that added together give a square (1334025 = 1155²).

The spelling of 685808648217 in words is "six hundred eighty-five billion, eight hundred eight million, six hundred forty-eight thousand, two hundred seventeen".