3999841 has 4 divisors (see below), whose sum is σ = 4084992. Its totient is φ = 3914692.

The previous prime is 3999803. The next prime is 3999851. The reversal of 3999841 is 1489993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1489993 = 43 ⋅34651.

It is a cyclic number.

It is not a de Polignac number, because 3999841 - 2¹³ = 3991649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3999851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42505 + ... + 42598.

It is an arithmetic number, because the mean of its divisors is an integer number (1021248).

Almost surely, 2^3999841 is an apocalyptic number.

It is an amenable number.

3999841 is a deficient number, since it is larger than the sum of its proper divisors (85151).

3999841 is an equidigital number, since it uses as much as digits as its factorization.

3999841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85150.

The product of its digits is 69984, while the sum is 43.

The square root of 3999841 is about 1999.9602496050. The cubic root of 3999841 is about 158.7380018626.

The spelling of 3999841 in words is "three million, nine hundred ninety-nine thousand, eight hundred forty-one".