685065640 has 32 divisors (see below), whose sum is σ = 1761598080. Its totient is φ = 234879552.

The previous prime is 685065631. The next prime is 685065673. The reversal of 685065640 is 46560586.

It is a super-2 number, since 2×685065640² = 938629862217219200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 685065593 and 685065602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1223052 + ... + 1223611.

It is an arithmetic number, because the mean of its divisors is an integer number (55049940).

Almost surely, 2^685065640 is an apocalyptic number.

It is an amenable number.

685065640 is an abundant number, since it is smaller than the sum of its proper divisors (1076532440).

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

685065640 is a wasteful number, since it uses less digits than its factorization.

685065640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2446681 (or 2446677 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The square root of 685065640 is about 26173.7586143068. The cubic root of 685065640 is about 881.5441380860.

The spelling of 685065640 in words is "six hundred eighty-five million, sixty-five thousand, six hundred forty".