685449511 has 4 divisors (see below), whose sum is σ = 685531224. Its totient is φ = 685367800.

The previous prime is 685449493. The next prime is 685449517. The reversal of 685449511 is 115944586.

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

It is a cyclic number.

It is not a de Polignac number, because 685449511 - 2¹³ = 685441319 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 (685449517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26620 + ... + 45601.

It is an arithmetic number, because the mean of its divisors is an integer number (171382806).

Almost surely, 2^685449511 is an apocalyptic number.

685449511 is a deficient number, since it is larger than the sum of its proper divisors (81713).

685449511 is an equidigital number, since it uses as much as digits as its factorization.

685449511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81712.

The product of its digits is 172800, while the sum is 43.

The square root of 685449511 is about 26181.0907144832. The cubic root of 685449511 is about 881.7087627211.

It can be divided in two parts, 6854 and 49511, that added together give a palindrome (56365).

The spelling of 685449511 in words is "six hundred eighty-five million, four hundred forty-nine thousand, five hundred eleven".