685995648 has 128 divisors (see below), whose sum is σ = 1979208000. Its totient is φ = 209264640.

The previous prime is 685995637. The next prime is 685995649. The reversal of 685995648 is 846599586.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 685995591 and 685995600.

It is not an unprimeable number, because it can be changed into a prime (685995649) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 653428 + ... + 654476.

Almost surely, 2^685995648 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 685995648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (989604000).

685995648 is an abundant number, since it is smaller than the sum of its proper divisors (1293212352).

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

685995648 is a wasteful number, since it uses less digits than its factorization.

685995648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1210 (or 1198 counting only the distinct ones).

The product of its digits is 18662400, while the sum is 60.

The square root of 685995648 is about 26191.5186272198. The cubic root of 685995648 is about 881.9428698965.

It can be divided in two parts, 68599 and 5648, that added together give a palindrome (74247).

The spelling of 685995648 in words is "six hundred eighty-five million, nine hundred ninety-five thousand, six hundred forty-eight".