309684685 has 16 divisors (see below), whose sum is σ = 384480432. Its totient is φ = 239296000.

The previous prime is 309684677. The next prime is 309684689. The reversal of 309684685 is 586486903.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 10982596 + 298702089 = 3314^2 + 17283^2 .

It is not a de Polignac number, because 309684685 - 2³ = 309684677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309684689) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13227 + ... + 28183.

It is an arithmetic number, because the mean of its divisors is an integer number (24030027).

Almost surely, 2^309684685 is an apocalyptic number.

It is an amenable number.

309684685 is a deficient number, since it is larger than the sum of its proper divisors (74795747).

309684685 is a wasteful number, since it uses less digits than its factorization.

309684685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15104.

The product of its (nonzero) digits is 1244160, while the sum is 49.

The square root of 309684685 is about 17597.8602392450. The cubic root of 309684685 is about 676.5604028278.

It can be divided in two parts, 30968 and 4685, that added together give a palindrome (35653).

The spelling of 309684685 in words is "three hundred nine million, six hundred eighty-four thousand, six hundred eighty-five".