3999646 has 16 divisors (see below), whose sum is σ = 6922080. Its totient is φ = 1697760.

The previous prime is 3999637. The next prime is 3999647. The reversal of 3999646 is 6469993.

It is a junction number, because it is equal to n+sod(n) for n = 3999596 and 3999605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216 + ... + 2836.

It is an arithmetic number, because the mean of its divisors is an integer number (432630).

Almost surely, 2^3999646 is an apocalyptic number.

3999646 is a deficient number, since it is larger than the sum of its proper divisors (2922434).

3999646 is a wasteful number, since it uses less digits than its factorization.

3999646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2739.

The product of its digits is 314928, while the sum is 46.

The square root of 3999646 is about 1999.9114980419. The cubic root of 3999646 is about 158.7354222256.

The spelling of 3999646 in words is "three million, nine hundred ninety-nine thousand, six hundred forty-six".