685431 has 6 divisors (see below), whose sum is σ = 990080. Its totient is φ = 456948.

The previous prime is 685429. The next prime is 685453. The reversal of 685431 is 134586.

It is not a de Polignac number, because 685431 - 2¹ = 685429 is a prime.

It is a super-2 number, since 2×685431² = 939631311522, which contains 22 as substring.

It is a Duffinian number.

685431 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 685395 and 685404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38071 + ... + 38088.

2⁶⁸⁵⁴³¹ is an apocalyptic number.

685431 is a deficient number, since it is larger than the sum of its proper divisors (304649).

685431 is a wasteful number, since it uses less digits than its factorization.

685431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76165 (or 76162 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 685431 is about 827.9076035404. The cubic root of 685431 is about 88.1700825614.

The spelling of 685431 in words is "six hundred eighty-five thousand, four hundred thirty-one".