685778734 has 4 divisors (see below), whose sum is σ = 1028668104. Its totient is φ = 342889366.

The previous prime is 685778719. The next prime is 685778767. The reversal of 685778734 is 437877586.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171444682 + ... + 171444685.

It is an arithmetic number, because the mean of its divisors is an integer number (257167026).

Almost surely, 2^685778734 is an apocalyptic number.

685778734 is a deficient number, since it is larger than the sum of its proper divisors (342889370).

685778734 is a wasteful number, since it uses less digits than its factorization.

685778734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342889369.

The product of its digits is 7902720, while the sum is 55.

The square root of 685778734 is about 26187.3773791879. The cubic root of 685778734 is about 881.8499023859.

The spelling of 685778734 in words is "six hundred eighty-five million, seven hundred seventy-eight thousand, seven hundred thirty-four".