685831680 has 360 divisors, whose sum is σ = 2547662832. Its totient is φ = 170459136.

The previous prime is 685831673. The next prime is 685831681. The reversal of 685831680 is 86138586.

685831680 is a `hidden beast` number, since 6 + 8 + 583 + 1 + 68 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685831681) 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 35 ways as a sum of consecutive naturals, for example, 6658509 + ... + 6658611.

Almost surely, 2^685831680 is an apocalyptic number.

685831680 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685831680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1273831416).

685831680 is an abundant number, since it is smaller than the sum of its proper divisors (1861831152).

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

685831680 is a wasteful number, since it uses less digits than its factorization.

685831680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The square root of 685831680 is about 26188.3882665581. The cubic root of 685831680 is about 881.8725964032.

The spelling of 685831680 in words is "six hundred eighty-five million, eight hundred thirty-one thousand, six hundred eighty".