685661760 has 280 divisors, whose sum is σ = 2788188480. Its totient is φ = 156681216.

The previous prime is 685661749. The next prime is 685661773. The reversal of 685661760 is 67166586.

It is a tau number, because it is divible by the number of its divisors (280).

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

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 179551 + ... + 183329.

It is an arithmetic number, because the mean of its divisors is an integer number (9957816).

Almost surely, 2^685661760 is an apocalyptic number.

685661760 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 685661760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1394094240).

685661760 is an abundant number, since it is smaller than the sum of its proper divisors (2102526720).

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

685661760 is a wasteful number, since it uses less digits than its factorization.

685661760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3815 (or 3796 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 685661760 is about 26185.1438796887. The cubic root of 685661760 is about 881.7997601797.

The spelling of 685661760 in words is "six hundred eighty-five million, six hundred sixty-one thousand, seven hundred sixty".