3685840 has 20 divisors (see below), whose sum is σ = 8569764. Its totient is φ = 1474304.

The previous prime is 3685837. The next prime is 3685849. The reversal of 3685840 is 485863.

3685840 is digitally balanced in base 2 and base 5, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2108304 + 1577536 = 1452^2 + 1256^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 3685796 and 3685805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3685849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22957 + ... + 23116.

Almost surely, 2^3685840 is an apocalyptic number.

It is an amenable number.

3685840 is an abundant number, since it is smaller than the sum of its proper divisors (4883924).

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

3685840 is a wasteful number, since it uses less digits than its factorization.

3685840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46086 (or 46080 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 3685840 is about 1919.8541611279. The cubic root of 3685840 is about 154.4704788888.

The spelling of 3685840 in words is "three million, six hundred eighty-five thousand, eight hundred forty".