3999940 has 24 divisors (see below), whose sum is σ = 9600192. Its totient is φ = 1371360.

The previous prime is 3999929. The next prime is 3999949. The reversal of 3999940 is 499993.

It is not an unprimeable number, because it can be changed into a prime (3999949) 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, 14146 + ... + 14425.

It is an arithmetic number, because the mean of its divisors is an integer number (400008).

Almost surely, 2^3999940 is an apocalyptic number.

It is an amenable number.

3999940 is an abundant number, since it is smaller than the sum of its proper divisors (5600252).

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

3999940 is a wasteful number, since it uses less digits than its factorization.

3999940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28587 (or 28585 counting only the distinct ones).

The product of its (nonzero) digits is 78732, while the sum is 43.

The square root of 3999940 is about 1999.9849999437. The cubic root of 3999940 is about 158.7393114923.

The spelling of 3999940 in words is "three million, nine hundred ninety-nine thousand, nine hundred forty".