685420 has 24 divisors (see below), whose sum is σ = 1474704. Its totient is φ = 267456.

The previous prime is 685417. The next prime is 685427. The reversal of 685420 is 24586.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (685427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 462 + ... + 1258.

It is an arithmetic number, because the mean of its divisors is an integer number (61446).

2⁶⁸⁵⁴²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (737352).

685420 is an abundant number, since it is smaller than the sum of its proper divisors (789284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685420 is a wasteful number, since it uses less digits than its factorization.

685420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 849 (or 847 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 685420 is about 827.9009602603. The cubic root of 685420 is about 88.1696108990.

The spelling of 685420 in words is "six hundred eighty-five thousand, four hundred twenty".