685521786 has 32 divisors (see below), whose sum is σ = 1489766400. Its totient is φ = 209496240.

The previous prime is 685521779. The next prime is 685521797. The reversal of 685521786 is 687125586.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 93456 + ... + 100523.

It is an arithmetic number, because the mean of its divisors is an integer number (46555200).

Almost surely, 2^685521786 is an apocalyptic number.

685521786 is an abundant number, since it is smaller than the sum of its proper divisors (804244614).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685521786 is a wasteful number, since it uses less digits than its factorization.

685521786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194034.

The product of its digits is 806400, while the sum is 48.

The square root of 685521786 is about 26182.4709681879. The cubic root of 685521786 is about 881.7397512720.

The spelling of 685521786 in words is "six hundred eighty-five million, five hundred twenty-one thousand, seven hundred eighty-six".