3990840 has 64 divisors (see below), whose sum is σ = 13685760. Its totient is φ = 912000.

The previous prime is 3990827. The next prime is 3990841. The reversal of 3990840 is 480993.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3990841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1536 + ... + 3215.

It is an arithmetic number, because the mean of its divisors is an integer number (213840).

Almost surely, 2^3990840 is an apocalyptic number.

3990840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3990840 is an abundant number, since it is smaller than the sum of its proper divisors (9694920).

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

3990840 is a wasteful number, since it uses less digits than its factorization.

3990840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4772 (or 4768 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 3990840 is about 1997.7086874717. The cubic root of 3990840 is about 158.6188409710.

The spelling of 3990840 in words is "three million, nine hundred ninety thousand, eight hundred forty".