686565685 has 16 divisors (see below), whose sum is σ = 891774576. Its totient is φ = 504419328.

The previous prime is 686565679. The next prime is 686565697. The reversal of 686565685 is 586565686.

It can be written as a sum of positive squares in 8 ways, for example, as 93837969 + 592727716 = 9687^2 + 24346^2 .

It is a cyclic number.

It is not a de Polignac number, because 686565685 - 2¹⁷ = 686434613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14004 + ... + 39613.

It is an arithmetic number, because the mean of its divisors is an integer number (55735911).

Almost surely, 2^686565685 is an apocalyptic number.

686565685 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

686565685 is a deficient number, since it is larger than the sum of its proper divisors (205208891).

686565685 is a wasteful number, since it uses less digits than its factorization.

686565685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53832.

The product of its digits is 10368000, while the sum is 55.

The square root of 686565685 is about 26202.3984589197. The cubic root of 686565685 is about 882.1870895601.

Subtracting from 686565685 its reverse (586565686), we obtain a palindrome (99999999).

The spelling of 686565685 in words is "six hundred eighty-six million, five hundred sixty-five thousand, six hundred eighty-five".