685608842 has 4 divisors (see below), whose sum is σ = 1028413266. Its totient is φ = 342804420.

The previous prime is 685608821. The next prime is 685608883. The reversal of 685608842 is 248806586.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 583174201 + 102434641 = 24149^2 + 10121^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171402209 + ... + 171402212.

Almost surely, 2^685608842 is an apocalyptic number.

685608842 is a deficient number, since it is larger than the sum of its proper divisors (342804424).

685608842 is a wasteful number, since it uses less digits than its factorization.

685608842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342804423.

The product of its (nonzero) digits is 737280, while the sum is 47.

The square root of 685608842 is about 26184.1334017378. The cubic root of 685608842 is about 881.7770744168. Note that the first 3 decimals are identical.

The spelling of 685608842 in words is "six hundred eighty-five million, six hundred eight thousand, eight hundred forty-two".