3640840 has 32 divisors (see below), whose sum is σ = 9362880. Its totient is φ = 1248192.

The previous prime is 3640829. The next prime is 3640843. The reversal of 3640840 is 480463.

It is a Smith number, since the sum of its digits (25) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (3640843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6222 + ... + 6781.

It is an arithmetic number, because the mean of its divisors is an integer number (292590).

Almost surely, 2^3640840 is an apocalyptic number.

It is an amenable number.

3640840 is an abundant number, since it is smaller than the sum of its proper divisors (5722040).

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

3640840 is a wasteful number, since it uses less digits than its factorization.

3640840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13021 (or 13017 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 3640840 is about 1908.0985299507. The cubic root of 3640840 is about 153.8392655890.

The spelling of 3640840 in words is "three million, six hundred forty thousand, eight hundred forty".