685400538 has 8 divisors (see below), whose sum is σ = 1370801088. Its totient is φ = 228466844.

The previous prime is 685400533. The next prime is 685400549. The reversal of 685400538 is 835004586.

It is a happy number.

685400538 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

685400538 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 685400496 and 685400505.

It is not an unprimeable number, because it can be changed into a prime (685400531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57116706 + ... + 57116717.

It is an arithmetic number, because the mean of its divisors is an integer number (171350136).

Almost surely, 2^685400538 is an apocalyptic number.

685400538 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

685400538 is a wasteful number, since it uses less digits than its factorization.

685400538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114233428.

The product of its (nonzero) digits is 115200, while the sum is 39.

The square root of 685400538 is about 26180.1554235264. The cubic root of 685400538 is about 881.6877638725.

The spelling of 685400538 in words is "six hundred eighty-five million, four hundred thousand, five hundred thirty-eight".