685639650 has 48 divisors (see below), whose sum is σ = 1717952544. Its totient is φ = 180948480.

The previous prime is 685639639. The next prime is 685639651. The reversal of 685639650 is 56936586.

685639650 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 685639650.

It is not an unprimeable number, because it can be changed into a prime (685639651) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9012 + ... + 38111.

It is an arithmetic number, because the mean of its divisors is an integer number (35790678).

Almost surely, 2^685639650 is an apocalyptic number.

685639650 is an abundant number, since it is smaller than the sum of its proper divisors (1032312894).

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

685639650 is a wasteful number, since it uses less digits than its factorization.

685639650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47235 (or 47230 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 48.

The square root of 685639650 is about 26184.7216903293. The cubic root of 685639650 is about 881.7902818414.

The spelling of 685639650 in words is "six hundred eighty-five million, six hundred thirty-nine thousand, six hundred fifty".