685366409 has 8 divisors (see below), whose sum is σ = 843528000. Its totient is φ = 542267856.

The previous prime is 685366369. The next prime is 685366411. The reversal of 685366409 is 904663586.

685366409 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-685366409 is a prime.

It is a super-2 number, since 2×685366409² = 939454229171110562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (685366439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3765659 + ... + 3765840.

It is an arithmetic number, because the mean of its divisors is an integer number (105441000).

Almost surely, 2^685366409 is an apocalyptic number.

It is an amenable number.

685366409 is a deficient number, since it is larger than the sum of its proper divisors (158161591).

685366409 is a wasteful number, since it uses less digits than its factorization.

685366409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7531519.

The product of its (nonzero) digits is 933120, while the sum is 47.

The square root of 685366409 is about 26179.5036049196. The cubic root of 685366409 is about 881.6731293051.

Multiplying 685366409 by its sum of digits (47), we get a palindrome (32212221223).

The spelling of 685366409 in words is "six hundred eighty-five million, three hundred sixty-six thousand, four hundred nine".