685736006778 has 48 divisors (see below), whose sum is σ = 1524303085032. Its totient is φ = 222666048000.

The previous prime is 685736006777. The next prime is 685736006827. The reversal of 685736006778 is 877600637586.

685736006778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 551034528489 + 134701478289 = 742317^2 + 367017^2 .

It is not an unprimeable number, because it can be changed into a prime (685736006777) 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, 215043 + ... + 1190678.

Almost surely, 2^685736006778 is an apocalyptic number.

685736006778 is an abundant number, since it is smaller than the sum of its proper divisors (838567078254).

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

685736006778 is a wasteful number, since it uses less digits than its factorization.

685736006778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1406431 (or 1406428 counting only the distinct ones).

The product of its (nonzero) digits is 71124480, while the sum is 63.

The spelling of 685736006778 in words is "six hundred eighty-five billion, seven hundred thirty-six million, six thousand, seven hundred seventy-eight".