4003994 has 4 divisors (see below), whose sum is σ = 6005994. Its totient is φ = 2001996.

The previous prime is 4003981. The next prime is 4003999. The reversal of 4003994 is 4993004.

It is a happy number.

4003994 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 2146225 + 1857769 = 1465^2 + 1363^2 .

It is not an unprimeable number, because it can be changed into a prime (4003999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000997 + ... + 1001000.

Almost surely, 2^4003994 is an apocalyptic number.

4003994 is a deficient number, since it is larger than the sum of its proper divisors (2002000).

4003994 is a wasteful number, since it uses less digits than its factorization.

4003994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001999.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 4003994 is about 2000.9982508738. The cubic root of 4003994 is about 158.7929216200.

Adding to 4003994 its reverse (4993004), we get a palindrome (8996998).

The spelling of 4003994 in words is "four million, three thousand, nine hundred ninety-four".