685215258 has 64 divisors (see below), whose sum is σ = 1741135872. Its totient is φ = 174882240.

The previous prime is 685215253. The next prime is 685215283. The reversal of 685215258 is 852512586.

685215258 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (685215253) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3316 + ... + 37167.

It is an arithmetic number, because the mean of its divisors is an integer number (27205248).

Almost surely, 2^685215258 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685215258, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (870567936).

685215258 is an abundant number, since it is smaller than the sum of its proper divisors (1055920614).

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

685215258 is a wasteful number, since it uses less digits than its factorization.

685215258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40539.

The product of its digits is 192000, while the sum is 42.

The square root of 685215258 is about 26176.6166262945. The cubic root of 685215258 is about 881.6083096838.

The spelling of 685215258 in words is "six hundred eighty-five million, two hundred fifteen thousand, two hundred fifty-eight".