3999424 has 112 divisors (see below), whose sum is σ = 10241280. Its totient is φ = 1520640.

The previous prime is 3999421. The next prime is 3999439. The reversal of 3999424 is 4249993.

3999424 = 332² + 333² + ... + 364².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999421) 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, 173877 + ... + 173899.

It is an arithmetic number, because the mean of its divisors is an integer number (91440).

Almost surely, 2^3999424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3999424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5120640).

3999424 is an abundant number, since it is smaller than the sum of its proper divisors (6241856).

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

3999424 is a wasteful number, since it uses less digits than its factorization.

3999424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78 (or 68 counting only the distinct ones).

The product of its digits is 69984, while the sum is 40.

The square root of 3999424 is about 1999.8559948156. The cubic root of 3999424 is about 158.7324853060.

The spelling of 3999424 in words is "three million, nine hundred ninety-nine thousand, four hundred twenty-four".