685187217252 has 108 divisors (see below), whose sum is σ = 1766629283328. Its totient is φ = 223915579200.

The previous prime is 685187217251. The next prime is 685187217283. The reversal of 685187217252 is 252712781586.

It is a happy number.

685187217252 is a `hidden beast` number, since 6 + 8 + 518 + 7 + 2 + 1 + 72 + 52 = 666.

It is not an unprimeable number, because it can be changed into a prime (685187217251) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 41652093 + ... + 41668539.

Almost surely, 2^685187217252 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 685187217252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (883314641664).

685187217252 is an abundant number, since it is smaller than the sum of its proper divisors (1081442066076).

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

685187217252 is a wasteful number, since it uses less digits than its factorization.

685187217252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16890 (or 16824 counting only the distinct ones).

The product of its digits is 3763200, while the sum is 54.

The spelling of 685187217252 in words is "six hundred eighty-five billion, one hundred eighty-seven million, two hundred seventeen thousand, two hundred fifty-two".